Well you had a lot of answers on this one eh! LOL
Orfe will spawn when the water temp is high enough and for long enough in the spring
We have 3 ponds which feed each other via waterfalls...2 are shallow but we did put fish in them...the longest pond had our Orfe...they bred...you do not have to do a thing as the eggs will hatch and some will survive....I have been informed and our grown on babies confirm it (at least in this case) that the Orfe will most likely cross fertilise with ordinary goldfish (in our case a Sarassa comet...the resultant fish are 'interesting' but the most interesting thing about the whole thing is that the VAST majority are ....BLACK...and once again water temp plays a huge part in whether they ever turn gold/white/etc. some of ours never have, and some most definitely did!
Hpe this 'belated' advice helps, give me a shout if you want a longer chat about it!