With 2-part clear resin, it really helps to warm up the molds, then mix-up the resin,
pour it in, then as the resin is setting, keep the mold and resin warm, a cheap trick
would be to find a cardboard box cut a hole in it for a hairdryer and keep the dryer on "Warm".
I hope that helps you out.
That technique has worked with the store-bought clear resins I have used in the past.
NOTE:
This needs to be done in a well-ventilated Garage because the resin smell
can be really strong and you don't want to breathe it in too much!