Settings are available from X-Plane's menu:
Plugin > LiveTraffic > Settings.... In the "Advanced" section you can tweak some rather internal parameters of LiveTraffic, which you should definitely understand before changing.
Log.txt logging Level
Amount of information written to X-Plane's log file
In case you can reproduce an error or weird behaviour then please set this to Debug before your reproduce once more. Then create a support request and attach the resulting log file.
Level of messages shown in the message area in the top right corner. Fatal shows least, Info most messages.
Only selected messages appear there at all. With this setting you can further reduce the number of messages appearing. Less than Warning is not recommended, however.
Max Message List Len
Number of messages kept for display in the Messages List
Max number of aircrafts
Maximum number of aircrafts to display.
Distance in nautical miles around current viewing position which is scanned for live flight data.
Snap to Taxiways
Aircraft positions will be updated to the closest taxiway or runway centerline, if there is such a taxiway/runway in a maximum distance of this many meters.
The feature is completely switched off (and scenery no longer read) if set to
Live data refresh
Number of seconds to wait between two queries for live flight data.
Note that data for any one aircraft does not update continuously. Querying data more often will not have much of an effect.
Seconds to buffer before displaying aircrafts. This serves as the look-ahead buffer for LiveTraffics data cleansing and take off/landing prediction and is equivalent to the time lag between LiveTraffic's aircraft display and reality. See an FAQ for more background.
A/c outdated period
If there is no data for this number of seconds then the aircraft is removed from display.
This setting should be greater than the Live data refresh period, otherwise aircrafts have no chance of collecting enough data for display.
Also see a FAQ on that.
Number of seconds a network request is allowed to take before considering it failed.
Note that OpenSky is known to sometimes respond sluggishly, taking up to 60s. Hence values below 60s are not recommended if using OpenSky for tracking data.
Display this Settings window as a transparent window just like the Aircraft Information Window. Changes to this toggle require you to re-open the Settings.
Opacity of both the Aircraft Information Window (where this same value can be change, too) and a transparent Settings window.
100% means full black background, 0% means no background at all.
The [Reset to Defaults...] button allows you, after a confirmation prompt, to reset all Advanced Settings to their respective defaults as documented here.