The problem "Job going through one branch of Split node getting stuck in the Join node" you described (earlier in this thread) with the Join node was fixed in 5.4.3. I assume this is the problem that is being referred to.
I have not been able to replicate the issue on FFCore 5.4.2. I do not know what your WF is exactly. Could you include the .ffc of your workflow? You'll need to change the extension to .zip when you upload it.
I get the exact same problem when I use collect on the imposition Node.
I also have a problem when I split. I have a workflow that we have been using for a long time that will take in a zip file that conatins has 50 books. I have a split node that strips off page 1, 2, 3 and 4 and sends them to a different branch, because these are perfect bound books. This branch has an imposition node in it to impose the pages into a signature and then it has the collect operation turned on to collect all of the jobs documents for that job into one file then I send this to a save node that saves into a hot folder that sends it to the printer. I do this save step using the following command "$FFwfJob.groupName$ - Covers" in order for it to retain the name of the zip file submitted. This has always worked in the past and we have been running this way for 2 + years. The pages go to a seperate branch to print as 8.5 x 11. Now what is happening is that the the file sits in the active Queue as Submission pending. Within this job the files have been duplicated and the ones that are collected and imposed are marked as complete even though they never make it to the printer and the other ones, the pages, are waiting for processing.
I have reversed the upgrade on our development server and gone back to 5.3.0. The exact same workflow is on our development server. I will be testing tomorrow and will let you know if the problem still exists but I have to say that I believe that it will not.