I *think* I did it. Very very veeeeeery basic controls for these two. Took me about 6 hours to mash together. Since I'm at work

The main file is called "Unicode-Test.pb" and is the file that runs all the other included code. The first include is "UnicodeInclude.pb" and contains a couple of helper procedures. The next is "uButtonGadget.pb" which contains the code to create a (hopefully) unicode Button gadget. Also, "uStringGadget.pb" is used to (really really hopefully) create a unicode String Gadget. Last is the INI file that stores the unicode strings. I include it as my little test thing but after you look at the code you can see how I interact with it and make your own INI file. Just remember it needs to be saved with Unicode encoding (see the ReadUnicodeINI() procedure in 'UnicodeInclude.pb' for reading values from a unicode ini file).
These aren't meant to be an end-all-be-all solution. Just mainly to see if it's possible. Again, Linux fellas, I'm sorry - I only know Windows development

I didn't really delve in deep and make these things super-solid. There are a lot of things missing, incomplete bug checking... yatta yatta yatta... I built them based off of my xMask control and then just changed things for unicode. Probably not speedy if you're doing a whole bunch of unicode reading & text setting at once. :shrug:
Anyway, I'll paste each of the files into a separate reply so that they don't hog up 1 post. Or at least, I'll try. Look at the example on how it's used.
Let me know if it actually works. As time goes on and no other better opportunities present themselves - I'll probably try adding more unicode gadgets and more functionality. I'll see about it while Fred works on PB 4.0. Creating a unicode button and string gadget is basically a test run to see if it's even possible to accomplish this in PB without doing totally weirdo stuff.
Have fun and good luck with it!

UPDATE
Okay, home now so here is the link to download all of them at once, including the unicode encoded text file. Be sure to update the location of the file in the test file.
Download here: Unicode Test