hey, hammy! :--)
try getting the CLICK as soon as the elbows hit the ground, and have the treat under his nose before he gets his shoulder down
to roll - this is a timing problem, U need to interrupt the *roll* before he commits to it.

if U have trouble getting down to him / bending-over to reach him, work DOWN on a hassock or other raised / padded surface;
test it when he seems to have it nailed by moving to the floor, if he fails there, Do Not CLICK but just move him back onto
the raised-surface + practice some more.

changing Ur cue, especially the hand-cue, can help him differentiate DOWN from ROLL.
just re-label DOWN with a new signal, and start over - the 2nd time is usually 10% of the initial
teaching / learning time, + with the new *clear* un-tainted cue, he should learn at light-speed.

all my best,
--- terry

__________________
terry pride, APDT-Aus, apdt#1827, CVA, TDF
*wolves R wolves, dogs R dogs, + primates R us.*
tmp, sept-2007