Everytime at final established ILS after capture of localizer and glideslope the aircraft can't hold G/S and lose altitude. I get warnings with "don't sink". This is during the last 2 nm before touchdown. It always catch up with G/S at the last moment. But the deviation from G/S is quit remarkable and it can result in touchdown very close to start of runway and sometimes it compensates with thrust very late and make touchdown far beyond the the ordinary touchdown area.

When this happen I am reducing speed towards appropriate landing speed according to the FMC.

Another thing I have wondered about is that of all the add-ons I use, 737PIC, LD767, PMDG747 and Maddog the CS757 have very low landing speeds according to the FMC. I find that a little odd. I would suspect that MD82 and B737 was supposed to have the lowest landing speeds in general. Maybe the calculations by the FMC is wrong in some way. I may be wrong but thats my guess. Example today with flaps 30 FMC said landing speed 127. I had ZFW 171000 lbs and about 3 tons of fuel left when landing.