Moving a 14 module app from Ant to IDEA

People,

I have made a little progress . . :

I have:
- a working ant build that runs the original Java app fine

In IDEA 2017.2 EAP
- imported the application and have got all 14 modules building with no errors
- installed eclipser and converted the launch file

However, I when I try and run the program I get:

Exception in thread "main" java.lang.NullPointerException
at java.util.Properties$LineReader.readLine(Properties.java:434)
at java.util.Properties.load0(Properties.java:353)
at java.util.Properties.load(Properties.java:341)
at com.thisiscool.honesty.common.PropertiesManager.getProperties(PropertiesManager.java:81)
.
.

Line 81 is:

properties.load(getClass().getResourceAsStream(resource));

I came across the same problem with the App when I tried to get it going with Eclipse about a year ago. It looks like if the code might run happily with the jar file and the classes that were built by ant? - but if the classes etc get rebuilt then this problem occurs . . The resource is a file called:

"app.properties.linux"

I tried adding:

";?*linux"

to Settings -> Compiler -> Resource Patterns with no improvement - from the suggestion here:

https://stackoverflow.com/questions/26328040/intellij-idea-getclass-getresource-return-null

Any suggestions about how I should proceed?

Thanks,

Phil.