MS Platinum 13 still has the Time Display window, which shows the current cursor position.
"Right-click the window and choose a command from the submenu to change the display format."

As you discovered (assuming you're on Platinum versions), the lower right corner boxes in the MSP 13 main window now display event length, selection length and project length. In previous versions (and still in VPro 13) they display cursor position, selection end and selection length. MSP 13 Simple Edit mode does not have these boxes.
I do not have the plain basic Movie Studio 13, but according to the MS 13 Application Help on this site it shows the current cursor position in the Time Display window as well.

I have got version 11 Vegas PRO and two PCs with Platinum for wedding films so I need the mode as advanced as possible... I need the informations about cursor : start + end + loop length - if the version 13 has not this, I don't understand...

lekki,
are you sure you are in MS Platinum 13 Advanced Edit mode? Click Advanced on the Main Toolbar.
As said in the previous post, you'll see the current cursor position in the time display window and event length, selection length and project length in the bottom right boxes.

This might be due to lower display resolution. On my netbook with only 1280x720 display resolution there either is no information on the right bottom of the timeline, except of Event length. If resolution is even lower you won't see any info.