UI for users that following the workflow

I am in the process of creating an UI for workflow process where the object (document) is moving by workflow. We have two sides: sender of document and acceptor.

This interface have to inform sender on which state of workflow the document stays currently and in case he can do something with the document, do that and send it to approval.

Acceptor changing the state of document (Stage and status), for him the element of UI works as a button to change the document status.

From the point of saving space in the interface, the best case is to use related dropdown lists. But they do not provide clarity.

I'm trying to use on linear view, as shown in the picture, but this not satisfy me, because the workflow can have a lot of stages and if we use linear view we have to make scrolling buttons on this scale. Where we have transition to previous stages, it is not very comfortable too.

I used icons for stages:

• Flag - as present state
• Lock - as unaccesible
• Target - as sign of accessible stage.

The matter is complicated by the fact that acceptor can select for the document the previous stages and the task executor must be informed at what stage he is now and from which stage he came there.