Export OMF From Samplitude Pro X to Reaper
Samplitude Pro X can export a project as OMF, with a couple of options worth setting deliberately.
Go to File > Export project as AAF/OMF, and choose OMF as the format.
You'll be asked whether to embed, copy, or just reference the original audio files, and whether to export stereo files as dual mono — useful if you know the session is heading to a strict Pro-Tools-style workflow, but not necessary just to convert it into Reaper.
Once you have the .omf, it still needs converting — Reaper doesn't open it directly.
You can convert your OMF file for free here.
A 2-minute walkthrough of how to open an OMF file in Reaper, from start to finish.
Everything you need to know about OMF files and Reaper: how to open an OMF in Reaper, how OMF exports work (embedded vs. non-embedded), what they contain, what's missing, and what used to break before this converter existed.