I am replacing 6 euro locks with anti bump/snap locks.
I have done four locks with no problem. But locks 5 and 6 are causing me major problems. Both are on UPVC double doors with lockmaster multi-point lock and yale euro locks. Both euro locks did NOT have the normal securing screw. But no matter how I try I can't get the euro locks out. They are loose and are moving backwards and forwrds by 5-7 mm. But no matter where I position the key they won't come out. Having already done four locks I no how they should come out. Is there some other hidden screw holding them in.
I badly need help - I now have 4 doors with good locks and two with std. euro locks. Please someone help me.

Gman, December 2008

Not an answer but I have got similar problem. I have removed the grub screw and there appears to be another hole about 15mm down. Is this where the hidden screw is?

referee, February 2010

solved the problem my self. No obvious fixing screw but lock held in place with a 35mm grub screw operated by allen key down the hole where normal screw would have been.

Gman, December 2008