I am also moving away from MAMUT in time. Probably end of year. I checked out Xero but it cant fulfil our needs by a long shot. I too found it way too basic in many ways. I'm considering Sage ERP X3 which seems to have it all.
Meanwhile I will indeed need a way to keep stock updated to avoid customers buying out of stock product or missing sales on replenished products. I see RedAnt has a tool called M-Port which hooks into MAMUT and exports data:
http://www.redant.nl/producten/m-port/
RedAnt states that they charge €750 per work-flow. i.e. If you need a data set to go from MAMUT to CSC then that's 1 work-flow. If you also need data to go back into MAMUT then that's another work-flow and costs another €750. I just need one direction. Which is already pretty costly with RedAnt. I am sure that there are developers who can do this for a reasonable price.
What I need is a script to check the correct MAMUT database (a database is basically a company in MAMUT) for the stock levels of products and options that are in CSC. One CSC category has discontinued products which do not need to be checked.
The product or option SKU in CSC corresponds with SKU in MAMUT. Then adjust the stock levels of CSC accordingly.
This process needs to run once a day.