The below are the important transaction which can be used by a person who is working on a Workflow Support Project.
1. SWI1 :To see any workflow log by just entering the workflow id ,this is very useful
2. SWIA :To process any workitem ,like completing workflow manually ,replacing workflow etc,this can be used. ( Process Workflow as administrator)
3. SWI5 :To check the inbox of any user and to see which are the workitem he has completed and he has to complete
4.SWPR :To Restart workitem after correcting the error in it. many times workflows goes into error so after correcting it you can use it.
5.SWWL :To delete the unnecessary workflows which came in a large number (in 100s 500s etc. ) through job processing and not of any use.In such cases just enter the task number of workflow and enter the date ,you can easily delete and help user by clearing his sap inbox.
6.SWDD : TO See any workflow definition,task details .each and every details can be find by this , by entering workflow definition number .
7.SWEC :To restart workflow after system crash .many times a workflow get hang on due to system crahs at any particular instance.just restart it and it will get process successfully.
8. PFAC_CHG :to make any change in workflow rule like changing the responsibilities under a rule,and maintaining position etc.
9.PFTC_CHG :To make any change in task like its description etc ,this is also very useful.
10 PPOME :This is very very useful transaction and we can see the complete org structure,position ,person assigned to position and change it accordingly.
11 PFOM : To see all the CLM (Customer Logistics Manager ) assigned to any sales area we can use this transaction.
12 SWU3 :To see each and every customization in system,workflow customization ,to check RFCs are working fine or not etc.
13. SWO3 :To see Business object builders like BUS2081 etc which contains the complete part like Methods used,attributes etc.
14. SBWP :To see your own inbox in SAP system.
15 : HRUS-D2 :This is not a transaction but it’s a table where we can see substitute maintained for any user.
16:RMPS_SET_SUBSTITUTE ; Whenever any user goes on any uncertain live and forgets to maintain substitute to app rove/reject documents then through this transaction we can maintain substitute for any user.
All these transaction are my hardwork of 2 years in workflow support and each and every transaction i used daily in any issue .
Hope it will be helpful for you.