So, you can go a few different routes, one of which you've already tried, making your own from Hardware store parts. But, using regular window screen is going to reduce your PAR from your lights immensely (even the clear 1/4" stuff that RedSea and others use reduce par by as much as 10-15%, with black/grey window screen, you're probably looking at a 40-50% reduction or more).
You can do one of the DIY kits, which sell extra parts for light mount cutouts, but there's no reason to believe that you will have any better luck cutting these than you did your own from the hardware store.
Lastly you can have someone make you some custom acrylic/polycarbonate + Screen tops.
TopLids - Expensive, takes forever, and their customer service has been lacking as of late according to a few forum conversations currently going on
Clearview Lids - still a relatively long lead time, and they use a really thick piece of polycarb or acrylic, but they come in slightly cheaper, and have more options than TopLids, and they can make their screentops longer than 24" without having to split into two tops, this is who my top is currently made by.
KrakenReef - The cheapest of the bunch, aesthetically not as cool as the other two, but definitely function well, use a thinner, and therefore lighter weight polycarbonate than the other two, but anything over 24" has to be cut into multiple pieces (So a 36" tank will be 2 18" pieces rather than 1 single piece).
If I was making the choice today, knowing what I know now, I would choose Kraken personally... I had one on my Flex, and it was nice, but I felt I wanted to try a different company on this tank, so I went with ClearView and I kind of regret it...