A couple of quick queries please Adil...

Does the fit of the T-Nuts in the Slots allow for a wee bit of sideways adjustment, or can you achieve this by using the M5 socket-screws in your rails?

I'm wondering whether it's best to go for high-tensile screws/bolts or whether A2 stainless is good enough....

Also where peeps have found a good place to source socket-head-screws? Did you just get them off eBay?