Suggestion for the wary, frustrated, want to do better, etc. -
How about joining together and support each other to build up your own Samples & Settings folder as you try and practise the exercises in this workbook - eg. 1 chapter per week.
The exercises can be done on any overlocker, so don't be put off that your machine is not the make or model in the workbook. Just have your manual handy.
Workbook Exercises for overlocker (& coverstitch)
It takes you through step by step and builds up your understanding and confidence.
By working on exercises instead of projects, you have permission to get it wonky. You have to make things wonky so you can get the hang of adjusting the different settings to get the result you want.
The idea is you - Use different coloured threads, Try the exercise, practise, deliberately get it wrong and become confident in troubleshooting and fixing, then make samples on the fabrics types you work with and record the settings for your machine.
If you want to watch the videos that demonstrate the exercises in the workbook -
see these videos here (Page 2 has the extra techniques eg. quilt as you go). The focus is on the 1150MDA but much of the information and techniques is transferrable to other makes and models.
Alternatively here is a useful collection of
Beginner Serger Tutorials (just get past the 'perky' voice). It's like a course. There are other collections, quite a good one is by an Australian and I think Jessie gave some links to those a while ago.
And, as the Brother 1034D has a different tension disk open/close system compared with other machines,
this video shows how it's important to use the tension release buttons on the top of each thread path when threading.
On other machines, lift the presser foot to release/open the tension disks for threading.
So how about you band together into a sew-along type group and do the exercises?