polysiloxane synthesis

I'm an experienced chemist but new to organosilicon chemistry.
Recently, I have been trying to synthesize a polysiloxane copolymer.
I'm using tetramethylammonium silanolate from Gelest as my initiator.
I've made 2 attempts so far - the first worked well but didn't have the
properties I was looking for. On the second attempt, I tweaked the
ratio between the cyclics I was using slightly and the reaction didn't
work at all! I'm hoping someone who has more experienced than I can
help me figure out what the problem is. Here are some things I am
suspecting:

1. On the first attempt, all reagents were used as received but were
opened right before I weighed and added them. I didn't take any
special care to keep the reagents dry, but I didn't let the bottles sit
around with their caps off either. Is the polymerization extremely
sensitive to small amounts of water?

2. On the first attempt, my reaction flask was brand new. I rinsed it
with solvent and dried it in the oven. On the second attempt, the
flask had been washed by our dishwasher. I again rinsed it with
solvent and dried in the oven before beginning. Could trace amounts of
soap be an issue?

Finally, can anyone recommend a practical guide to silicone ROP? I
have read a lot of literature but have yet to find many places where
practical lab information is provided.

Thanks in advance for any information.

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