As an exercise I decided to convert my TM1637 driver from Spin to C. I still need to document the code, but it does seem to be working properly.
An interesting note... converting the Spin code to C caused me to think about the str() function differently. I went back to the Spin version and was able to improve the speed of str() by 2x, and give it better behavior vis-a-vis strings with decimal points. The two versions are identical now.
Any feedback you care to offer is appreciated.