Hi Pete,
Since you have the setup mind testing my conversion process as well?
Second, I would reinforce Mickpat's suggestion. Take a look at the seq file with a hex editor. to make that easy I would say make a sequence that alternates at 50 millisecond timming on channels 1-3 and channels 4097-4099. using the same pattern (i.e. when channel one is on channel 4097 is on, 2 same as 4098 and 3 same as 4099).
the first four bytes in the seq file will be channels 1,4097,8193,12289 and the next four bytes 2,4098,8194,12289.
So if channel 1 and 4097 are on in the first time frame bytes 1 and 2 should be the same value in the seq file. If they are not then the conversion is errant.
To look at the next time mark you will need to go to byte 16385 (4001 in hex). The bytes there follow the same pattern as mentioned above (i.e. 16385 = channel 1, 16386 == channel 4097 etc...).
This should validate if LSP is putting data in the right places during the translation.
Frank