[Hooston]

A variety of "typical shabby Nazi tricks" are available.

A convoy spawns into 3D at a range of 32km (for me with GWX). This causes the game to lag, the size of the lag depending on the number of ships. This is of course an accurate simulation of the Kaleun's sixth sense for danger.
In a similar vein the maximum time compression is limited when the boat is under threat (e.g. spotted by the enemy), and the crew tend to cower and look worried. Different time compression limits correspond to different levels of threat.

Once the convoy has spawned and you have an idea of the bearing it is possible to lock on to individual ships with the Uzo or periscope even if they are too far away to render. Just keep spamming the lock on 'L' key whilst tracking across the bearing. The lock is held for about a minute. If external views are enabled you will then be able to browse the ships you have locked using ',' and '.'. If on the surface the watch officer will also be able to give range and bearing of the nearest target. I always say this compensates for a lack of a "smoke on the horizon" feature. Or in fact the lack of any horizon at all in the base game. I'm kidding myself of course - it just saves a lot of pfaffing when trailing a convoy.
For really advanced cheating i guess you could use the mission editor to work out when and where to go. This is very good for finding minefields. Yes there are loads of mines in GWX, in the locations you would expect, but they are spread very thinly and you usually sail straight through them without noticing.
Hope this doesn't spoil the game for you! You "need to be strong in this war" to eschew all the cheats the game offers, especially the superhuman weapons officer...