Yeah i had the same problem with that Waddah_Attar_Explosion indicator, just downloaded it off mql4 codebase plopped it in the indi folder and havn't heard any hoo ha since.

As for those S1 send errors you're most likely using a lot size too small on the backtester than your broker supports so take it up to 0.1 or 1 instead of 0.01 if thats what your doing, just for the meantime.