With the help of various purebasic fellows from the purebasic community,
I managed to get callbacks to work from newlisp-dll.
Here is a complete purebasic source with the newlisp utf8 dll (32 bit):
Screenshot:

By the way: One of the reasons why purebasic is a good companion to newlisp is the size of the final exe which is here 49 KB.
For 64 bit purebasic user the 64 bit Dll must be downloaded from newlisp.org.
Regards
Hans-Peter