hiya. Here's how...
With REAPER closed...
Either Start>Run or open Windows Explorer with the Address Bar visible and then type...
%APPDATA%\REAPER\REAPER.INI
This will open your INI file where you can then insert a new line directly under the [REAPER] first line and give the location of your chosen splash image in this format:
splashimage=c:\locationofimage.bmp
You'll probably find it makes sense to put a dark stripe along the bottom where the status text will appear in white as REAPER and your projects load up.
Personally I think it's only fair to put the Cockos logo and the word REAPER in the design somewhere out of respect for Cockos letting us personalise in this way
but hey that's just my view!
Hope that helps
drew
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Proudly using REAPER exclusively for...
* Media and event music composition & production, sound design + auto-processing at
Qsonics.com
* Broadcast branding, promos, education & training and narration voice-overs at
DrewWhite.com