I noticed that setting up Sprites ADF would be much easier if we could display a bounding box of the adf mesh by pressing "y" on Sprites_ADF operator. Is that possible to implement? Thank you.

yes you're right. it also concern sph colliders.
sphSimpleCol now has his box. for the next, soon

Very well. Thanks. I will get back this evening.

Yes! Works great. Awesome!