Connecting transmission and motor when you tighten the two together the crank will not turn?

Assuming this is an automatic transmission, you didn't install the torque converter all the way back into the transmission. If you put any amount of pressure trying to mate the two by drawing in on the bellhousing bolts, you have probably damaged the front pump in the transmission. Take the transmission back out and try to work the converter back into the trans all the way by rotating and wiggling the converter. If the converter doesn't drop back all the way, take the trans to a shop for repair.