I don't know much about the LOR setup, but here are a few of the hints I do know.
In xlights, the order on the setup page is critical. The column to the far right shows you the channel numbers in LSP or vixen.
If your LOR controllers are the first channels, that entry has to be at the top of the list.
E1.31 universes are 512 channels. I'm not sure what effect setting them to 510 has...
Different versions of LSP have different channel number limits. The version I have stops at channel 8192. Channels 8193 and above will not be transmitted or exported. I think there is a version that only does 512 channels, and another version that is unlimited.
There are a number of LOR users on this list, so give it some time for them to chime in.
Good luck!
RM