I changed the code of your module to be more flexible. It finds the right name of the installed version of libnewt.so and uses this one. I think, this is somehow like the use of libraries should be implemented in such modules.
Code Select
(context 'Newt)
(define (find-libnewt)
(if (!= (setq result-of-find (exec "find /usr/lib -name *libnewt*")) '())
((exec (string "basename " (last result-of-find)))0)
(throw-error "libnewt not found in /usr/lib! You might need to install libnewt.")))
(constant 'Prefix "newt")
(constant 'Library (find-libnewt))
However I got this error message trying your example:
My guess is, I'm using another libnewt library.ERR: import function not found in function import : "/usr/lib/i386-linux-gnu/libnewt.so.0.52.14: undefined symbol: newtComponentGetPosition"Quote
called from user function module