This is a peculiar problem, which is difficult to help solve, partly because you have given no indication of what version ArchiCAD or PlotMaker you are using. By the looks of your attachments, you have upgraded to AC9 & PM9. In that case I don't know why you would prefer to use PMK's instead of linked views. You could probably increase your efficiency by 20% - 50% using linked views, especially if they are pre-linked.
Anyway, assuming you didn't open the PMK and manually change the lighter line around the sink, it sounds like a pen mapping problem. What makes me curious is that you said "I opened the PMK file and the lines are correct, both in terms of weight, color, etc." How did you so this exactly? Did you simply double click on the placed PMK file, or did you go to File>Open...? I can only assume that is was the latter, because PlotMaker is WYSIWYG and if you have mapped the pens (intentionally or not) the colors and line weights should be the same on your sheet as it is if you open the PMK by double-clicking on it.
There are two ways to map pens & colors in PlotMaker. One is to use Uniform Pens & Colors. You can check if this is the case by going to Options>Preferences>Drawing Attributes... If it is checked on then you can change the pens & weights (of the entire layout book) by going to Options>All Pens & Colors... and editing the pen (weights) & colors there.
The second method is if you are not using Uniform Pens & Colors. This way each placed PMK or view can have it's own unique pens & colors. To do this, select the PMK and edit it's settings (Ctrl/Cmd+T). Uncheck 'Pens & Colors' under the 'Attribute Update Rules' tab and hit the 'Edit Pens' button under the 'Attributes' tab. Then you can change the pen (weights) & colors as before.
To add to this you can transfer these pens and colors to other placed PMK's/views by using your eye dropper and syringe tools as in ArchiCAD. Or more efficiently you can select all the required PMK's/views in Drawing Usage and hit the 'Settings' button at the bottom of the Navigator. I will also soon be adding a tip to 'Working in ArchiCAD' that demonstrates how to transfer you ArchiCAD pens & colors to the entire PlotMaker book.
Check the PMK's pens & colors and let us know how you go. If all else fails you may have to upload a stripped down version of the LBK.
Cheers,
Link.
