I would never, ever go flat. You are asking for a lot of trouble. The best system is the K2 dome illustrated previous. Once you get water ingress the panel is shot.
Thats Panel Claw, Sunfixings sell it in the UK they call it Light Tegra
Renusol do a new metal post that can be ballasted or fixed and felted over I think - FS10
Nicholson roof track do a system that can be secret fixed and felted into the roof - ROOFTRAK? | Nicholson
Perhaps the nicest one though is from Danish company Jual - JUAL which can be retro fitted to felt and they're real nice guys, speak to Henrik
Don't forget most manufacturers have a limitation of min 5˚ pitch in their warranties, of course you could fit Solar Frontier as they don't have pitch reliant warranties, but sounds like space might be an issue.
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