If just doing basic stuff, eps export should be fine or Ai export.
But if you have gradient fills in Signlab i would recommend that you install the Apple Color Laser Writer printer into Windows via Add Printer from Control Panel. Then, set the Port location of the Printer driver to File.
Then from Signlab, instead of Exporting, go File/Print and print to the Apple Color Laser Writer printer and when prompted for a File name, give it an EPS extension.
Transferring gradients from one program to another is a struggle but the Apple color laser printer driver seems like a good universal translter.
And as Brian said, use “eps interpreted” in Corel to import
frank at cadlink