As my previous reply pointed out: in the BeginPage event handler, the BeginPageEventArgs provides the information you need.
The code would be like:
void MyPlotReactorManager_BeginPage(object sender, BeginPageEventArgs e)
//Get Layout name the current plotted page is plotting
//Then, you can open a transaction to get Layout object, hence, its name
//Get scale, depending on whether standard or custom scale is used
Note, the code is just off my head and not tested, but you get the idea: just digging into BeginPageEventArgs's PlotInfo property would get all information you need.
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