Changing the colour of the inside and outside contour

Hi.

I would like to change the inside and outside contour colour.  (as people send me layouts where the colour needs to be changed)

I haven't figured out a way to do this easily. The files I get do have text (where the outside contour should not be changed but only the inside contour) and lines (where only the outside contour color needs to be changed)

Iam using the "find and replace" feature in corel but I need to do this for the inside contour and I need to do it again for all outside contour paths.
And... as I need to select a colour which needs to be replaced, chances are that the customer send me objects which have a slightly different colour and these colours will not be affected by the "find and replace" function as I can only select one colour which needs to be replaced.
Also this function made some errors by not selecting anything - for whatever reason. (couldn't find the problem yet)

I'd seen within other it works within 2 seconds.. by just selecting everything and then change the colour for everything at once.
https://www.youtube.com/watch?v=bYWYmgaDvQw&feature=youtu.be

Iam hoping that iam just stupid and iam missing the function in Corel? (I tried combining or grouping the objects but that did not work)
If the layout has text with inside contour and some lines with outside contour and I select everything... by using the left mouse button and right mouse button clicking on a colour then the text will also have an outside contour - which is wrong. (it should stay the same as it was before)

I could move all lines to another Layer but that lasts a long time (like using find & replace) and chances are that Iam missing something and then the layout has errors.

Any ideas?

Thanks!