Don't know if you're still watching the thread, but I'll take an initial stab and perhaps with the "bump" others will chime in. This is not really my area, but here are some initial thoughts.
A basic rule is that there can be no copyright on facts as facts, only on how those facts are expressed.
In a situation where a test is created to elicit factual answers -- without repeating exact phrasing of passages created by the author of the text on which a test is based -- it's hard to see how copyright would come into play. The only potential copyright issue that occurs to me is if a publisher might try to argue that keying test questions to chapters of the textbook constitutes copying the "selection and ordering" of the facts of the text. Personally I feel that would be a stretch, but those active in copyright might have another take on that.
Trademark law concerns itself with making sure that people can trust that goods or services sold in connection with the trademark come from the trademark owner. Where it is clear that the person referencing the trademark is not using it as a designation of origin for his/her own goods or services, generally there is no trademark issue in simply using the trademark as a reference to the actual trademarked product (which is not to say that an aggressive trademark owner might not try to make an issue of it). For example, it is not a "trademark use", and therefore not infringing, of the marks "EPSON" and "HP" to say that a printer ink cartridge is compatible with "EPSON" model xyz or "HP" model abc printers.
All that being said, remember that it is entirely possible for you to be in on good ground legally but still get sued by someone who thinks their rights are greater than they are. You would do well to consult your own IP attorney before getting this project off the ground, just to be sure you understand what would be the likely safe parameters and the potential risks.
As for the use of thumbnail pictures, that would involve both copyright and trademark and others in the forum will be better able to speak to that.