Snap to grid lines when moving verticle acros the path I need create new verticle on path in point where grid and path are crossing.



How I make it:
1. Select points
2. RMB and subdivide
3. Select new verticle
4. Shift + V to move across path
5. Trying to move it with CTRL SHIFT and ALT modifiers  

Sometimes it works



Sometimes not



How it works in inkscape



Maybe trere is easiest method?
ok this might be a funny solution but it works!


your line
make a line with e to desired location and connect to other with f
do the same to other side
join two new verts with J
clean the verts with ctrl + x