I installed the trial (and all of your installers btw, or at least this one and the one for action, are not UAC compliant, which should be corrected) and splash pro ex just won't run unless I run as admin.
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[CRITICAL ERROR]
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Failed to initialize product. Please try reinstalling.
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OK
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Sorry, but I won't be buying a video player that requires elevation, but I thought I'd tip you off about how to at least make it UAC compliant.
My guess is that in the manifest file, you've specified for splash to run with highest privileges available. Unfortunately this won't cut it for "Standard" users.
This isn't made clear at all by Microsoft, but it is always advisable to use a "Standard" account, and to create a separate admin account that you don't log into- only to be used in conjunction with UAC. UAC compliance effectively means, your program runs in the userspace and the main process should never be elevated. If elevation is required, a sub process should be spawned and ask for elevation via UAC, it should be aware that it is no longer in userspace and thus should not rely on anything in the user's profile folder, and it should self terminate when the task is complete.
I don't know why splash wants to be elevated from the start- hardware acceleration is not something that requires administrative privileges...