The version that you want to use was written for the GP32, and you have the same amount of ram within the JL16.As for porting to the JL16, you could start by taking the file "IOGP32.H" and create an "IOJL16.H" from it. This is where all of the hardware address definitions are handled. You would then change the project to include your new .h file in place of the GP32 version.
The size of the .s19 file is only 2k, so it should fit with your application in the 16k of flash within the JL16.
The OS only uses only one of the JL16's two timers, so there is one left for your application. Also, it appears like the OS does not use the timer pins or channels, only the overflow (but I did not look close enough to be sure).
#ifndef XXXXXXXin order to avoid double declaration.
#define XXXXXXX
code
#endif