Dahlias - cuttings and pinching out - please help,!

Rosiebeaton

hello lovely gardeners, 
trying my hand at dahlias in pots this year, started off three different tubers of a shorter variety indoors in February. 
Two have got going really well and the third, Gallery Rembrandt, has not. Should I just keep waiting?
Also, I would love to take cuttings, based on height and number of shoots in my pics, can I do this? One only has 2 main shoots the other has about 6. 
As these are shorter varieties growing to about 50cm do I still need to pinch out and is this at the four pair of leaves stage? I am a bit bamboozled by it all 🤓
Many thanks 

fidgetbones

They need to be somewhere with plenty of light but  cooler. It has to be frost free, but they look like they are getting too much heat and not enough light.  Pinch the tops out of all shoots with more than two pairs of leaves. They will not be suitable as cuttings.

Rosiebeaton

Ok thank you - sorry I moved them from the window sill to take a picture! Is a south facing windowsill too warm then? Many Thanks