help!!!

So, I bought my 1986 Ranger XLT over half a year ago. in January, I had an engine from an '87 B2 installed by a reputable shop. Now I'm having 3 issues that are more than likely linked in some way. First, the truck doesn't "kick off" in the traditional sense. More like it just "sustains"...

i have an 85 bronco 2 with its original 2.8 5 speed. i also have a 2000 ford mustang with a 3.8 automatic . i would like to take the 3.8 out of the mustang and swap it with my 2.8 . I know there is a tech article on this but it jumps around so much it do not really tell me what i want to know...

I swapped the transmission and the thing will not shift. Even when manually shift from 1st to 2nd with no change in rpm or speed. Things I have checked Vacuum, fluid,and electrical connections. What could be the problem. I want to drive her, but I don't want to burn up a new tranny. Please help