Just thought I would post this in case someone runs into this same issue. It's pretty specific.
We use a 3rd party software for translations called Pointfire by a company called Icefire. I have run into issues when my workflows are larger (I have 2MB and 4MB workflows that have this issue). When the Pointfire tool is enabled, it causes these workflows to just display blank on the workflow designer when I try to edit them. I have to disable pointfire in order to do any edits.
On smaller workflows, certain actions will not be available to modify in edit mode, like condition actions. They will let you click Edit but not display any of the options, just a blank box.
The major issue, is when we try to migrate the workflow to another environment. We take a backup of the content database to migrate the site collection, then we import the workflows we have previously exported from the source site. If the site collection backup was made with Pointfire enabled, you will never be able to import the workflows. You have to completely disable Pointfire on all levels of that site collection, then do your backup and it will work.
I know it is not advised to have workflows over 500KB to 1MB, but this can probably still have effects on moderatly large workflows.
Hoping this can save someone some time.