Hi Mario,
Horizontal layout of sequential workflows is not provided out-of-box. However, if you choose to create your own designer on top of Windows Workflow Foundation (WF) you could control the layout.
We may or may not look at this in the future. What is the importance of this for you, and why? (Knowing that would help us evaluate and prioritize suggested feature adds/changes correctly.)
Thanks,
Anna Lidman - MSFT
Lead Program Manager | Connected Framework (WCF, WF) | Community & Release Mgmt |