Hi.
You cannot. You have to calculate x, y and add them to your OpenUserObjectWithParm command:
int li_ret
int li_x, li_y
// calculate li_x, li_y
li_ret = this.OpenUserObjectWithParm(n_cst_myuserobject, "param1", li_x, li_y)
But you also need to know your userobject's width and height to do the calculations. These can be found like this:
int li_ret
int li_x, li_y
integer li_width, li_height
n_cst_myuserobject luo_cst_myuserobject
luo_cst_myuserobject = create n_cst_myuserobject
li_width = luo_cst_myuserobject.width
li_height = luo_cst_myuserobject.height
if isvalid(luo_cst_myuserobject) then destroy luo_cst_myuserobject
// calculate li_x, li_y
li_ret = this.OpenUserObjectWithParm(n_cst_myuserobject, "param1", li_x, li_y)
By the way, as your userobject is visible and not non visual, it's name should start with u_ (u_cst_myuserobject).
Andreas.