When this: respawnTemplates[] = {"MenuPosition"}; is in Description.ext and respawn positions are added with Bis_fnc_addrespawnpositon function then the following error appears:
//=======================
Error in expression <uPosition_systemSelect",false]
&&
count BIS_fnc_respawnMenuPosition_positions > >
Error position: <BIS_fnc_respawnMenuPosition_positions > > Error Undefined variable in expression: bis_fnc_respawnmenuposition_positions
File A3\functions_f\respawn\fn_respawnMenuPosition.sqf, line 293
//==================================
The error does NOT appear when the respawn positions are defined with markers e.g respawn_west, respawn_west_1..
Also, except for the error, the respawn menu seems to work fine. You can select positions, the selection shows on the respawn map and the player respawns in the correct location.