When viewing a milestone with a forward slash ("/") in its name and a few tickets with dependencies, the link "Depgraph" in the upper right corner is shown correctly. But the linked page contains only an empty image without content.
It seems that when parsing the URL, only the part of the Milestone name up until the first forward slash is taken as the ticket milestone, resulting in an empty list of tickets.
E.g. for a milestone called "GUI/HW separation", I see this query like this in the log file:
SELECT t.id AS id,t.summary AS summary,t.owner AS owner,t.type AS type,
t.status AS status,t.priority AS priority,t.component AS component,
t.time AS time,t.changetime AS changetime,t.milestone AS milestone,
priority.value AS priority_value
FROM ticket AS t LEFT OUTER JOIN enum AS priority
ON (priority.type='priority' AND priority.name=priority)
Note that the 'GUI' in the WHERE clause should have been 'GUI/HW separation'
I use the distributor supplied version of this plugin, but I had a look at the diff between that and the "official" download: https://github.com/coderanger/trac-mastertickets/tarball/master . The differences are minimal and do not seem to include changes to the URL parsing.