Need Help with Menu Layout

you shall have an area "Dimensions" where to set the dimensions and offsets

I do not see an area for Dimensions, only Submenus Management, Margins, Background, Rounded Corners, Shadow, and Borders.

In the Submenus Management area, I have the Submenus width set at 918px. I see below that an option for Horizontal gap for sublevel. I tried adding a value here but that did nothing.

I see below that an option for Horizontal gap for sublevel

yes, this is what you must use to move the submenu.

Yes, I tried entering a value here, but it did nothing to move the sub menu. Setting a value in the "top gap" field works, but no the "horizontal gap". The submenu is currently right aligned and I tried adding a positive and negative value in the horizontal gap field but they did not have any effect. I would like the submenu to move left 38px.

I got this to work. In the module on the Effects Options tab, I had Overflow Detection set to Yes. When I set this to No, the horizontal gap option now works.