Thanks for the advice chaps. I prepared some ilfostop at 35 degrees but - alas - when I finally get everything ready to go, the bulb went kaput just as I was lining up the first negative.
Without any spares, that was that. It's just as well it did fail, as up until that point I was rather confused as to why the image on the baseboard was so dark when the aperture was wide open. Close inspection of the bulb (halogen for the Durst M605) revealed that it was highly knackered with all the reflective bits worn away.
That's what you get for buying a enlarger head 'as seen' without looking it over properly.
Anyhow, I'm intrigued by your suggestions of using trays instead of a drum - at room temperature. Does this work well with the Kodak RA4 chems, and by room temp do you mean 20 degrees C? I rather thought it had to be done at 35 or else...
Many thanks once again for all your comments.