helo h
yes the diseq switch works fine, i use one with my f1-ci.
instead of the monoblock [combined] Lnb, you can buy a small bracket and attach a extra Lnb and connect this and you original one to the switch.
it is best to direct your central Lnb to Hotbird as the signals from this one are not quite as strong as the Astra 1 at 19.2, then offset the second one.
it really is quite easy to do as long as you dish is fairly accessible.
you can either run two cables back to you STB then install the switch there 'in the dry', or install the switch near the dish and run a single cable back to the box.
you will need to assign appropriate Lnb's to the various channels you have loaded, and then all you have to do is select the station and the switch will do the rest.
if you have any problems do come back, or hop over to the Humax Users Group which you can find via the Moderator's site at:
http://x-stream.fortunecity.com/laras/21/index.html
the moderator, iain kendall is a very helpful and knowlegeable chap.
good luck
w. hole