CATIA won't draw 1

[MechEngMartin]

CATIA's sketcher no longer allows me to draw profiles with the mouse cursor. Even after selecting a circle, rectangle, etc to draw, the cursor remains as the regular arrow rather than the cross, and the coordinates for the particular shape all stay at 0 rather than following the cursor's motion. Alternatively, the drawing cross cursor will appear immobile at the origin, then when i try to manipulate it in any way, it disappears and a small "dead end" sign (red circle with white horiz bar) follows my cursor aroung, lagging heavily. Previously, I was able to draw without problems and with minimal lagging, and other software such as SolidWorks still works fine on my computer (AMD turion64 2GHz, 1024MB RAM). I even tried reinstalling CATIA and also resetting all the settings under 'options', to no avail. The program also lags in general now, such as when I pan the blank sketch.
Thanks in advance.

 

[Azrael]

Judging by your pictures you have to large zoom on and "snap on point" active so you can't snap on anything due to next point isn't visible. Zoom out or turn off "snap on point" (icon on upper bar that looks like a point on a grid))

 

[MechEngMartin]

You were exactly right, everything works fine now, thanks a lot.