When it comes to debugging no one is expecting you to know what it says ... and not necessarily what to do about it. But one could copy what it says ... come back here, and post a response with 'heres what debugging showed'!
Think Justin is the author of one of those plugins ... now when was the last time you got to talk to any programmer for Google, or Bing, or Windows, or Apple, etc..
That's what open source is about. Moodle is open sourced software and even though releases of versions have the word 'stable' in them doesn't mean it's 100% bug free. Moodle HQ releases code/updates to existing supported versions all the time ... at least once a week.
Now let's put that into some terms in your area ... Course Designer. Let's say you discover a 'better way'. Those folks for whom you have designed a course, might need your help in setting up this 'better way'. They also might have a hard time with the concepts and understanding 'why it's better'.
So take this little bump as just that ... a bump ... In a journey into expanding what you do ... a course designer with a + in troubleshooting issues + fixing them (even if you don't program) actually might lead you to expansion into other areas ... apache web services ... DB server admin. Those are things that are in the background but very important in making it go. A course designer with that sort of background has to be worth more than one without, right?
Kinda like Bachelors, Masters, and Doctorates degrees, huh?
The 'ride' can be frustrating at times ... but all the bumps and ups/downs in emotions will make you a better course designer in the long run.
Testing things out on a laptop version of Moodle is a good approach to start ... if that blows up, no biggy ... you are then forewarned and might be better prepared for the production server then.
'spirit of sharing', Ken
PS .. we 'old folks' really aren't any smarter ... we just have had more experience - good as well as bad. We're just able to recognize a mistake when we make them again ... cause we've made 'em before! ;)