I installed OU wiki on standard Moodle 1.9 using the standard theme.

When using the annotation feature as follows:

<<
Click Annotate tab. Verify that annotation marker images are displayed between
words and in other locations. Bug: image doesn't load. Click to add an
annotation at the end of the first line containing the text A1, and an
annotation at the end of the second line containing the text A2. Choose the
option to lock the wiki page. Save annotations.
>>

I noticed that the images did not load.

Also when viewing those annotations as student, there are images (maybe
different ones) which don't load.

I suspect these images are stored in the OU theme; the system should be changed
so that it uses the image from the module, but it can be overridden in the
theme. This means putting the images inside the module folder and referencing
them in the same way that forumng does flags.

If this guess is correct, then just changing theme to standard theme will
reveal this problem (ie it will still happen on OU moodle).

This is a guess and the problem could have another cause...