When first collecting images, particularly when I’m doing proof of concept test development, using the default image names image0001… imageYYYY makes some sense. However, when done you may want to name your images with something useful, like “AcceptButton”, or “SubmitButton”, or even “AvatarOfCurrentUser”, the latter maybe a collection if you are testing multiple users in a chat program for instance.
As for path setting, I have found organization of images to discover/test for is best done in a well defined and thought out hierarchy of test and project folders with the Images folder. However, if you must externalize your images for various reasons (maybe for archiving or flexibility purposes in theme or design changes), simply do as you have discovered and set a ProjectImagePath variable (use whatever name you want) and then use the following idea here shown in pseudo code.
to masterHandlerName params
set ProjectImagePath to “/Path/To/Images/For/This/Test/”
repeat with each in “TestOneName,TestTwoName,…,TestNName”
send it with params as parameters
Hope this helps, the ideas are more important than the untested pseudo code provided above.