Try Microprotol. This package comes with various design code options (ASME, BS5500, AD Merkblatter etc.) which can be purchased as separate modules. It also has the ability to produce drawings from the resultant calculations by it's own in-built CAD program and has ACAD and Microstation modules available also for further drawing enhancements.
It is marketed by D-MAC Engineering who should be available through the following e-mail link.
D-MAC Engineering GmbH [support@d-mac.com]
Dave McCutcheon is the manager.