upvc French patio doors

[xfr]

Just fitted the doors today.fixed door sides with metal straps fixed to inside block work.But have not fixed the centre and its flexing.
What is the best procedure to get round this,Its a galvanised lintel above.

 

[pinenot]

Get yourself some drill and tap screws, that when put in can be backed off/tightened to level off top runner. They need to be long enough to get through both sides of the profile but with the self countersink on the screw head will sit tucked in in a channel unobtrusive...pinenot