A few months have passed, and now a new person has these problems too!
In my case I think it's a conflict between SparkLE and my Focusrite 2i2 ASIO drivers (but still not sure) since if I switch to ASIO4ALL I can get some limited fuctionality but the sound is only through my computer speakers.
I have the Focusrite 2i2 and also a Creative/E-Mu 2x2 MIDI interface each installed with their respective drivers and it seems that something in this setup is making SparkLE incredibly unreliable - to the point where I can't come to record an idea with any confidence that I will get the system to work at all.
The SparkLE surface usually doesn't connect to the software either standalone or in a DAW (Sony Acid Pro 7 and/or Ableton Live 9 Lite) even when
neither DAW has selected the SparkLE ports. I'm getting to the point where I will either go back to a hardware drum machine and abandon any idea of involving a computer in the recording process (always thought it might be a bad idea, and I'm sadly feeling vindicated). The strange interaction between my Focusrite 2i2 and the SparkLE is my present avenue of research, and I'm wondering whether the 2i2 (which uses Focusrite Drivers but shows some default drivers were also being used) is sharing a driver with the SparkLE - which I believe uses standard Windows drivers (I'm on Windows 8.1) and, even though one is an audio device, is confusing the SparkLE into thinking it doesn't have exclusive access to its ports (or something).
Bit sad to have a room full of dedicated hardware that I can switch on and work with, and a computer for minor sequencing and SparkLE that is a struggle and a gamble every time I boot it up. Seems that even with 25 years in IT there are still murky patches to discover. Hoping I can get things to work. If I make some kind of miraculous breakthrough I'll post it here (I've had a few false starts!). For now, it's just a freakin' nightmare.
