James,
There may be just a .LIB file, no .DLL, check the manual. Is there any DLL in the download?
CDStartSDK -- to use it in FoxPro you probably need to know the description of the cdVersionInfo structure. The declaration itself should be very simple, something like this
DECLARE INTEGER CDStartSDK IN ??? STRING @pVersion, LONG Option
then
DECLARE INTEGER CDFinishSDK IN ???
and so on.
I have Canon Rebel XT, will take a look. It may happen to be an interesting subject.