Rob, I found this in the database which should be exactaly what your looking for:
select *
from dbo.actionstatestrings
ACTIONSTATE ACTIONSTATESTRING
0 Not Relevant
1 Evaluating
2 Running
3 Fixed
4 Failed
5 Locked
6 Waiting for Downloads
7 Waiting for Restart
8 Waiting for User Input
9 Constrained by Retry Delay
10 Constrained by Action Dependency
11 Constrained by Time Range
12 Constrained by Date Range
13 Constrained by License
14 Constrained by Distribution Time
15 Constrained by Active User Condition
16 Constrained by Properties Condition
17 User Cancelled
18 Download Failed
19 Waiting for User Login
20 Expired before execution
21 Postponed by User
22 Restart Waiting for User Input
23 Invalid Action Signature
24 Restart Cancelled by User
25 Constrained by Client Version
26 Action Files in Use
27 Pending Offer Acceptance
28 Offers Disabled
29 Constrained by Client Setting __BESClient_Download_PreCacheStageLimitMB
30 Constrained by Client Setting __BESClient_Download_MinimumDiskFreeMB
31 Download Hash Mismatch
32 Transcoding Error
33 Pending Client Restart
-1 <error>
-2 <error>
-3 <error>
-4 <error>
-5 <error>
-6 <error>
-7 <error>
-8 <error>
-9 <error>
-10 <error>
-11 <error>
-12 <error>
-13 <error>
-14 <error>