How to open the corresponding other window from schematic/layout window?

Hi,

I'm trying to open a corresponding schematic design from the layout window in IC18.7 using "_lxOpenSourceWindow(?windowId hiGetCurrentWindow())" and it works great.

Whats the similar function if i've to open a layout design from the schematic window? (Not gonna take Launch->Layout XL as an answer)

Also, how can i do the same thing in IC12 (where i can not use the above function) without going through the pop-up GUIs?

I'm not trying to open the other design in L mode, but in XL mode with all the connectivity reference.

Thanks

Ram