Hi again, Kabocha will go up a fence if that is what you want but they won't climb in the true sense,eg like an ivy would, you will have to tie them in as they grow.
I never pinch out my squash unless it is close to the end of the season and they are still producing babies. In that case I will pinch the growing to allow the already growing fruit a good chance on maturing.
Lots of folks will disagree with pinching out, but my own feeling is if the ground is well prepared and they are given the room they need to grow they don't need it.
If of course you are aiming to grow a record breaker then it is a good idea.
Bear in mind the growing needs and the length of time to harvest, there is vast differences between squash varieties. and plant accordingly. If you plant in time you should have no problems with Kabocha.
I have one full lottie of just squash which sometimes has more than fifty different types growing, the ground turns into a forest of foliage which would be impossible to go around pinching out.
So tips
Sow early enough that the plants have a chance of maturing in the UK, but not too early that they are cold.
Very well fertilised ground.
Be prepared to assist with water.
They need warmth so a bad summer is not good for squash.
Give them the space they need, cramping them is probably the number one mistake that people make.
Find the specs on the variety you want to grow so you are familiar with the time to harvest.
That is it really, given their needs I find they grow themselves.
Hope this helps.
XX Jeannine