For the most up to date terms see: https://hs-soft.com/assets/doc/restricted/Professional%20Service%20SLA%20EN.pdf

Liability
H&S shall not be liable for damages which can be traced back to modifications to the licensed software, which were not undertaken by H&S and for damages which can be traced back to external causes (including other programs).
H&S shall not be liable for slight negligence. Liability for consequential damages (including loss of earning) is excluded.
In all cases, the liability of H&S is limited to a liability sum based on the customer license sales by the affected customer of the last 12 months, irrespective of whether the claim giving rise to liability results from this agreement or from rules on contracts for the benefit of third parties.
If the licensed software are products of third parties, H&S shall only be liable for damages in case of its own fault.