Update BP Sun Position with slider UE 4.23

I have a project in UE 4.23 (for the need of html export) and made a project with a BP Sun position.

Now I have made a widget slider and want to set the sun hours and minutes. First I had the slider set in sun hours (from 8 am till 8 pm) but the sun rotates then in quite big steps of an hour.

What I want is to gradually slide the sun. So per minute base. I ran into the problem, that the node Solar time isn’t available in this UE yet. So I made the BP widget as follows:

I understand why the minutes is’n working (just for the first 59 minutes it’s fine) but after that it isn’t working anymore.
What I want to achieve is an slider (now set to 720 minutes = 12 hours) that counts with the slider the minutes and update the Sun, and after 59 minutes also count the hours +1

And it has also to work backwards from 20pm to 8 am.

But I don’t know how this setup properly?
Can anybody give me some tips or advice?

Thanks in advance!

I have tried some other things to make it work. I can make it work for the hours. But the counter I need for the minutes isn’t working well.

I guess I need a sort of “converter” for the minutes? Or am I thinking way to difficult?

Some advice will be helpfull, thanks!