We process small and fragile embryo tissue on a short programme 15 
mins/station. Starting with 30%,50, 70,90, 100 + 2x Xylene, 4x Paraffin.
BUT you should use the Histoscreen cassettes. These protect the specimen 
and reduce mechanical damage. I have tested these against all other methods 
(sponges/filter paper/agar etc.) the preservation is always superior.

Gud' Luck,

Keith Rogers