For the edge termination detail, I would have to know if the screws penetrate into a wood surface behind the sheet metal walls.
What I am most concerned about, especially since Florida has strict wind codes, id the fastening into the uni-lock standing rib covers. That metal looks to be the flimsiest version of 28 Gauge, which would not support fastener withdrawasl.
Also, I can not imagine instaling a flexible thermoplastic over the unsupported gaps between the ribs. Those lower recess cavities should have been filled up higher than the rib height to prevent excessive wind baffling and fluttering of the membrane.
I am convinced, from these photos, that that roof is destined to be blown off, by the negative pressure causing the membrane to pull the fasteners out. Initialy, prior to being blown off, the membrane will probably pull out somewhat and be sliced to ribbons by the metal edges and ribs.
Do you or your father happen to know which brand of membrane this was? If so, you could contact the manufacturer for their specifications and detail drawings.
I can not conceive that this woulf fly as an approved installation method.
The 3 most used brands of white thermoplastic membrane in the Florida area that I have heard about, are;
IB Roofing Systems
Duro-Last Roofing Systems
I certainly hope that I am wrong about this situation, but you might want to look up a member here, by the User Name of **“Cerberus”, **and PM him and e-mail him with a link to your photos and this topic thread. He is an intelligent Roofing Consultant, with a background in actual roofing installations, who could possibly shed some additional light on the subject.
Plese keep the posting updated to see how things work out.