Hi, Marco
Here are some advices on how you can speed up adding shapes to your diagram and layouting them:
1. Disable the automatic generation of unique names for the active layer. It’s faster if you provide names to the shapes using their Name property.
document.ActiveLayer.AutoGenerateUniqueNames = false;
2. Put the code that adds your shapes into a document BeginInit(), EndInit() block:
document.BeginInit();
// Add your shapes here
document.EndInit();
3. Regarding the layout – the symmetrical layout is a force directed layout, so you can use its MaxIterations and MaxTime (specified in milliseconds) properties to control how the amount of work and the time the layout is allowed to perform. Note that decreasing the maximum number of iterations (or time) will make the layout finish faster but the results may not be as good as if it was working longer.
Best Regards,
Nevron Support Team