Guideline 1. Support accessible authoring practices.

Checkpoints:

1.1 Ensure that the author can produce accessible content in the markup language(s) supported by the tool. [Priority 1] (Checkpoint 1.1)
If there is a source editing mode then this can be done - alternatively, if all elemments of the markup language can be used it is met. If not, check against the W3C Notes access features of HTML/CSS/SMIL, or specification for the markup used (e.g. PDF, etc)
1.2 Ensure that the tool preserves all accessibility information during authoring, transformations, and conversions. [Priority 1] (Checkpoint 1.2)
Take content with as much accessiblity information as possible and run it through the possible transformations
1.3 Ensure that when the tool automatically generates markup it conforms to the W3C's Web Content Accessibility Guidelines 1.0 [WCAG10]. [Relative Priority] (Checkpoint 1.3)
I have been testing this by contradiction. It would be nice if there were test suites or test tasks available - I believe the ER group is working on them. Note that this is a relative priority test, so trying to do the things that are outlined in the WCAG checklist by priorityt level is helpful - if it fails at level A then it has failed at higher levels (although it is useful to know more details)
1.4 Ensure that templates provided by the tool conform to the Web Content Accessibility Guidelines 1.0 [WCAG10]. [Relative Priority] (Checkpoint 1.4)
Manual checking of the templates (assisted by various tools - see WAI-ER' list of existing tools, the work by the EO group on review, etc).

Guideline 2. Generate standard markup.

Checkpoints:

2.1 Use the latest versions of W3C Recommendations when they are available and appropriate for a task. [Priority 2] (Checkpoint 2.1)
Check the W3C Technical Reports page for applicable specifications. Typically XHTML, PNG, XML, XML namespaces, Including Stylesheets in XML, MathML, CSS...
2.2 Ensure that the tool automatically generates valid markup. [Priority 1] (Checkpoint 2.2)
validate output.
2.3 If markup produced by the tool does not conform to W3C specifications, inform the author. [Priority 3] (Checkpoint 2.3)
If the tool can be made to produce markup that is non-conformant to a w3c specification, do it and see if it informs the author

Guideline 3. Support the creation of accessible content.

Checkpoints:

3.1 Prompt the author to provide equivalent alternative information (e.g., captions, auditory descriptions, and collated text transcripts for video). [Relative Priority] (Checkpoint 3.1)
Import a document containing images, movies, server-side image maps, applets and scripts, and see if there is prompting available to point out that some of these are missing alternative content. Add the elements and see if there is pormpting.
3.2 Help the author create structured content and separate information from its presentation. [Relative Priority] (Checkpoint 3.2)
Is it obvious how to create structured markup or is it a natural part of the process, or are you prompted to do it in accessibility checks?
3.3 Ensure that prepackaged content conforms to the Web Content Accessibility Guidelines 1.0 [WCAG10]. [Relative Priority] (Checkpoint 3.3)
Same testing as 1.4.
3.4 Do not automatically generate equivalent alternatives. Do not reuse previously authored alternatives without author confirmation, except when the function is known with certainty. [Priority 1] (Checkpoint 3.4)
Insert images / movies / etc and inspect the source.
3.5 Provide functionality for managing, editing, and reusing alternative equivalents for multimedia objects. [Priority 3] (Checkpoint 3.5)

Guideline 4. Provide ways of checking and correcting inaccessible content.

Note: Validation of markup is an essential aspect of checking the accessibility of content.

Checkpoints:

4.1 Check for and inform the author of accessibility problems. [Relative Priority] (Checkpoint 4.1)
Is there some form of accessibility check? If so, does it cover the WCAG checkllist (to what priority level - this is a relative priority).
4.2 Assist authors in correcting accessibility problems. [Relative Priority] (Checkpoint 4.2)
Is there a correction wizard, or help documentation associated with accessibilty checking?.
4.3 Allow the author to preserve markup not recognized by the tool. [Priority 2] (Checkpoint 4.3)
Make up some arbitrary source (or modify something existing by adding some garbage markup) and see if it can be imported and preserved (it is legitimate for the tool to refuse to process further...)
4.4 Provide the author with a summary of the document's accessibility status. [Priority 3] (Checkpoint 4.4)
Yes/No test...
4.5 Allow the author to transform presentation markup that is misused to convey structure into structural markup, and to transform presentation markup used for style into style sheets. [Priority 3] (Checkpoint 4.5)
Is there a way to transform markup that converts from styles to markup and presentation markup to style + structure markup?

Guideline 5. Integrate accessibility solutions into the overall "look and feel".

Checkpoints:

5.1 Ensure that functionality related to accessible authoring practices is naturally integrated into the overall look and feel of the tool. [Priority 2] (Checkpoint 5.1)
While testing other checkpoints, are the solutions part of the standard interface or do they require some other technique (source editing in a WYSIWYG tool, setting configuration options, ...
5.2 Ensure that accessible authoring practices supporting Web Content Accessibility Guidelines 1.0 [WCAG10] Priority 1 checkpoints are among the most obvious and easily initiated by the author. [Priority 2] (Checkpoint 5.2)
Are the functions needed to meet WCAG P1 requirements in front of the author, or do you have

Guideline 6. Promote accessibility in help and documentation.

Checkpoints:

6.1 Document all features that promote the production of accessible content. [Priority 1] (Checkpoint 6.1)
Check. This requires extensive knowledge of the tool and the documentation to do properly.
6.2 Ensure that creating accessible content is a naturally integrated part of the documentation, including examples. [Priority 2] (Checkpoint 6.2)
Check the help examples against WCAG
6.3 In a dedicated section, document all features of the tool that promote the production of accessible content. [Priority 3] (Checkpoint 6.3)
Is there an accessibility section in help? Is it complete?

Guideline 7. Ensure that the authoring tool is accessible to authors with disabilities.

Checkpoints:

7.1 Use all applicable operating system and accessibility standards and conventions (Priority 1 for standards and conventions that are essential to accessibility; Priority 2 for those that are important to accessibility; Priority 3 for those that are beneficial to accessibility). (Checkpoint 7.1)
Any hints people?
7.2 Allow the author to change the presentation within editing views without affecting the document markup. [Priority 1] (Checkpoint 7.2)
Can the author add a user style sheet, or specify a presentation format other than the published format (e.g. disable the specified style sheets and inherit system values)?
7.3 Allow the author to edit all properties of each element and object in an accessible fashion. [Priority 1] (Checkpoint 7.3)
Is there souirce editing available? Is there a property editor for elements which includes available attributes? (see also guideline 2)
7.4 Ensure that the editing view allows navigation via the structure of the document in an accessible fashion. [Priority 1] (Checkpoint 7.4)
Is it possible to move around the document element by element?
7.5 Enable editing of the structure of the document in an accessible fashion. [Priority 2] (Checkpoint 7.5)
Can elements be cut/copied/pasted as elements?
7.6 Allow the author to search within editing views. [Priority 2] (Checkpoint 7.6)
Is there a search funstion?