A large number of companies use specialist software or have special additions to standard software. For example software may need to be changed to operate tills and interface with a standard package.
We find that a great deal of frustration often arises when corrections are not put in place and various issues crop up. Again, as in other blogs, software developers with good systems do not cause issues.
The solution is to keep a log and an action plan.
Every time a new issue arises add it to the log. A Log can be lists in word or on a spreadsheet or any other means. Number the issues. The key thing is to log and report the issue preferably by email so there is record. Keep all the emails together.
Meet with the developer, this can be on line. Develop with them a timescale for the issue to be resolved and agree any costs. Record that timetable in your log by saying who is going to do what and by when. Keep supplying a copy of this action plan to the developer until the issues can be marked as complete. When you send an update set the reminder for the next one in whatever way you set reminders.
Persistence is the key. It must be clear there will be no escape!