first off,choice in tape#1 is Tesa,made in Germany[and like my buddy Vince on the Shamwow comercial says"we all know Germans Make good stuff

"] get it from Bron tapes of so cal. 800-354-5379. choice #2 3ms scotch 233+[the green stuff] its ok,had some issues with glue residue in the past,but not too bad. Tesa is way better.
As to your second problem,if im reading right,some xtra layers of tape here and there to protect the underlying tape levels may be needed. apply them smartly to come off after you have pulled your lines. this will protect the underlying lines and cover tape from overspray buildup.
when taping the mold you need to be thinking 4-5 steps ahead,in regard to how its going to be pulled.I can give you pointers but sorry experience can not be taught,it must be learned,the only way to learn is to do.IM going to say even get a flat table mold,and screw around a little.practice multi layer taping and spraying.As you run into problems,think about how you could have taped it differently to avoid the problem and try it next.
If i remember right you said you have some experience with exterior painting? 80% of what you know in that world you need to lock away in your head, away from this process and approach this with an open mind.