Thanks for your comment Geert_2, but I really dont think irt should be all that difficult. "Engineered to perform, the Ultimaker 2+ is reliable, efficient, and user-friendly. Thanks to its support of a wide range of materials, it’s suitable for a huge variety of applications, from prototypes to customized tools. " Thats what the Ultimaker saus in their website, and " Optimized for:PLA, ABS, CPE, CPE+, PC, Nylon, TPU 95A". So I expect to be able to du just that. And while I have lots of tools (including all the tools you recommend), I do not intend to spend a lot of time one what should have been a good print in the first time. I am having the printer looked at by a technician right now, I hope that will improve things. But frankly, if Ultimaker printers do not handle ABS well, they should be honest about it on their website.
regards, Maarten