MaxWedge426
Are you using conditional tags at the topic level?
If you are, you'll probably find that the 'Conditional Build
Expression' set on the first screen of the Printed Document dialog
actually excludes the topic you've included in the Chapter Layout
on the second screen.
The blue icon occurs when you have moved the topic from the
left pane to the right pane. If you've moved an entire book from
the TOC and there was a topic under that book that will be excluded
because of the Conditional Build Expression, the topic icon in the
right-hand browse turns grey - indicating it will not be used.
You'd need to change your conditional build express to
include the tag on the document.
Hope this helps.
Regards