The ghosting against the wall was something I never noticed (before). I did notice little metal clamps, presumably where the timber frame was attached to the wall. You probably know this already, but the post set into the wall, just visible on the left of your photo, is one of a pair, and these formed a gate/gateway (now bricked up), with the miscellaneous industry, on the far side of the wall.
The Weighbridge is not "propped up", although you could be forgiven for thinking so. This is Network Rail's obsession with installing flying buttresses. Here, a few long screws/bolts would've been far more suitable. All that happened was some cladding sagged under the weight of a particularly heavy downpour, when it emerged the gutters is more firmly attached to the cladding, than the cladding is attached to the frame. One corner of the building settled a bit further into the ground than the others years ago, and while that's now completely stable (and verified by a buildings surveyor), whoever assessed the cladding sag perhaps mistook them as linked. I am a bit concerned though, that pushing a stable building may cause issues down the line.
The roof on the visible side, last time I checked, had been re-slated and was fine. There is the danger that vandals may scale the buttress though. I've noticed someone has chucked bricks/stones through the previously-pristine upstairs windows - highly irritating.
I did used to keep the area immediately around it tidy, but I haven't been able to this year, due to stress-related illness and a back injury flaring up. I've just started a new job, so my stress levels are much better, and I haven't managed to re-injury my back yet, so I aim to return to this task: The number one rule of security, after all, is to keep external appearance clean & tidy. There's a CCTV gap (apart from when a train passes - as you doubtless know, they have outward-pointing CCTV), and the station/carpark improvements will close this gap, and any further opportunity for vandals. The end of the lockdown and warmer weather will help too. There's a block of flats directly opposite, and a high footfall, so it's not exactly deserted.
The South carpark is also due to be tarted up, and the plans for that are more mature. There will be a better taxi rank (although they always grumble nomatter what's proposed), better integration of the carpark near Sainsbury's Local, and bigger bicycle stands with a roof and CCTV. On the North side, the footbridge will be altered, as analysis shows they accidentally exposed pedestrians to a dangerous blind junction. The North carkpark entrance needs work. GWR had a cunning plan (demolish the Weighbridge), which is stupid, because they'd have to demolish half of Union Road along with it; all Listed buildings, most of which they don't own. Even then, a new junction with New Road there would be awkward to say the least. I have a much better plan: Change the entrance to the back of the current carpark, cutting through the fence from the upgraded Foundry Lane. I am not the only person to notice this solution: Network Rail usually cut through the fence for heavy plant access. Various nearby shops etc have also put in plans for it, although as all of those were submitted before the rerouting of Foundry Lane, getting the main road right appears to have been the overriding priority - it's eventually going to be a mini-bypass, taking the pressure off Pew Hill. Currently, it's primarily a gift to Aldi, where it currently terminates.