Sorry for the delay, @Victoria_Roz !
I just updated TRmesh and TRfem. Please update both (through PackageManager, unless you downloaded them directly for some reason), and then have a look at this example file. This should answer your question how to make the “black” TRmesh work with TRfem. Please let me know how it went, thanks!
trfemex11.gh (326.1 KB)