Whereas, the JCS.exe shipped with 1.10o does not contain a "Battle, Treasure, or CTF MultiPlayer level" checkbox in its Level Properties window;
Whereas, no level shipped with either 1.10o or Battery Check has the byte corresponding to that checkbox as any value other than 0;
Whereas, setting that byte to 1 has no visible effect in-game (it doesn't even alter the horizontal vs. vertical splitscreen stored in the previous byte);
I propose that the multiplayer byte in BC/1.10o-versioned .j2l files (version 0x202 but without a copyright header) be used to specify whether a .j2l is for 1.10o (value 1), Battery Check (value 2), or ambiguous (any other value at all including 0).