Good luck to you! I really liked the BTCC before the rule changes, which seem the same in the packet. As you are just playtesting you probably won't have the issue of the rec guide units being totally busted.
For missions, I recommend making the BV portion of the score BV/100 for destroyed, half for crippled. In the packet currently you max the score after killing 2000 BV, so like 1 big mech. We we played the BTCC missions, the game often ended early as someone hit 100 points after just a few rounds with 1 single kill plus a few turns on the objective.