Broadcasted server public variables are not available in client preInit.
That's a major issue as it also affects paramsArray which is also not available on clients in preInit.
Debug output looks like this in client RPT:
[33567,893.745,0,"Executing fn_preinit.sqf"]
["preInit value of client pvtestvar:",any]
["preInit value of client paramsArray:",any]
[33567,893.77,0,"fn_preinit.sqf processed"]
[35964,897.012,0,"Executing init.sqf"]
["init.sqf value of client pvtestvar:",1]
["init.sqf value of client paramsArray:",[1]]
[35964,897.012,0,"init.sqf processed"] {F22637}