Allow to set precise location of the startpoint

[Nandox7]

The current method to set a custom startpoint is drag &drop.
This does not allow for a precise location, for example if I want it to be at the exact center of a circle.

It would be really helpful if:

• Software calculate and given the option to set it at the exact center of a drawing
• Have the option to manually define and edit the startpoint location (same as is possible for the Reference point)

Thanks