I added a plg strip to an existing circuit,and plugged fluorscent fixture into strip.I then wired a switch and plugged it into strip. Off the switch I ran two 14/3 cables with plugs on the end to be used with portable lights.When switch is on everything works fine, but when I turn switch to off position the breaker trips.I tried a different plugstrip with same result.I then bypassed
Plug strip and plugged switch directly into outlet and then fuse blows.

What? "I then wired a switch and plugged it into strip."

This may be your problem. If the switch is across the hot and neutral of the plugstrip, when the switch is on it will be dead short.

Really need to know exactly how this is wired, wire for wire. Pictures will help a great deal.