I can relate. I too have CIS-Basic on my 16V. I can help with issue #1.
CIS-Basic doesn't have ISV, but on Mk1s, they used an auxiliary air regulator that pretty much did the same thing an ISV did.
When you start the car cold, you should hold it at 2K rpms for about a min or so. Afterwards, the engine will idle just fine. I have an aftermarket water temp hooked up to mine and I take my foot off the gas when it gets to 100*F and the car idles fine afterwards
I had a thought and idea which I will get around to doing eventually. The auxiliary air regulators plug is only consisted of 2 wires. One is for ground and the other is for a switched 12V. It too has no ports just like a stock 16Vs ISV does except where the 16V ports are aimed left and down for the vacuum hookups, the auxiliary air regulators is aimed left and right. If and when I get around to doing mine, I would make a custom bracket to have it mounted in between the 2 intake manifold runners and positioned just where it sits a little bit over the fuel lines. Pretty much I would make a bracket mounted to one of the studs where the upper and lower intake manifold meet. Then, I would route the vacuum lines, one coming of the intake pipe and the other one to the cold start valve connecting pipe.
I hope you can understand and this gives some insight as well.
Sorry I can't help on issue #2