Dr_Ju_ju

As I use BackyardEOS to control my DSLR, I save all the images to either the local computer, or directly to a network storage location....

If you use the external desiccant tube, then you can't use the front 'solid', so to avoid the fan outlet grills, you are forced to use the rear parts which make for a very front heavy mounting, unless you design something that can also have some front support...

A variation on the above, especially if you have\access to a 3D printer, its relatively easy to knock up something that can hold a pair of M4 bolts (I think that's the size, but may be M3) to do the job...

From experience I'd forget the 10M active cable, as I've never found them any good..... IF your set-up is permanent, then I'd consider sighting a small single board computer (Raspberry Pi3\4, Pine64 Pro's etc...) at the scope and then controlling everything inside... If everything is running on the SBC, then interruptions due to bad connectivity won't matter so much.

All my Win systems have been 64 bit for years, and as long you have the appropriate 64 bit drivers, for those bits of kit that require them, then you should be fine... Bare in mind that you can still run 32 bit code, and most of the applications that you want to run, will still be 32 bit, its usually specialist, targeted apps that make full use of a 64 bit platform.

sounds like the ubiquitous problem with USB leads....

I also run the USB2 version in conjunction with the 1600, using the 1600's hub with filter wheel & never had a problem, but the all other connected devices are connected through dedicated USB hubs either 2 or 3... If you're brave\confident enough, it may also be worth checking how much throughput you're actually getting on the USB ports, following this (How can I view USB device bandwidth allocation in Windows 10 - Microsoft Community) will at least show you what your getting & whether there are any bottlenecks...

Don't know the mount, but usually the central grub screw is what applies pressure between the gears, reducing slop\backlash. Just don't over tighten, else the axis will be difficult to move and may bind.

There are motorised DOB mounts, but for DOB's, and Fork mounts, both axes motors must be driven, to counteract earth rotation, but for EQ mounts only the Azimuth motor needs to be driven to keep focused on the target....

Very simply, and you don't say what type of mount you're asking about (Alt/AZ, Equatorial, manual, motorised etc.), but in general, If everything is properly balanced, then friction of the gears meshing together, due to the weight pushing down. will 'hold' the mount in the same position, but slewing the mount around will obviously move the balance point, and so 'push' the mount to a different position. Note there are additional friction locks on each axis, if you wish to stay in one place, but the target will move out of field of view due to the Earth's rotation etc.

Back to basics.... Does your new laptop have 'standard' usb3 ports and or any usb2 ports ? also do you have any short, good quality , usb cables cables and maybe a good quality external hub ? If you then connect each device singly, and monitor the computers device manager, especially looking for 'un-recognised devices', but also at the same time have system event viewer open & monitor what windows thinks is going on...

If you prefer RDP over VNC (personally I do), why not install xRDP (xrdp by neutrinolabs), you can then just remote desktop into each remote host, whether that be windows or linux based....

They may not be exactly the same, but they are on ebay i.e. https://www.ebay.co.uk/itm/Wiska-10102370-EVSP-12-Vent-Plug-Black-RAL-9005-M12/143939453837

Is the right location set in the EQMod control panel ??, i.e. expand the panel, with the spanner >> icon at the top ....

If you can find the size of the thread (diameter & pitch), then I'm sure one of those industrious chaps north of you (for OZ that is), may well be able to supply something close to what your after e.g. https://www.ebay.co.uk/itm/M8-M10-Steps-Knurled-Thumb-Screws-Aluminium-Handle-Stainless-Steel-Thread-Rod/124161416204 or AliExpress etc....

you also need to ensure that the USB controller devices (Device Manager) are all set, such that the power management, is set that "Allow the computer to turn off this device to save power" is disabled....

Don't forget the drivers for all the hardware.... plate solving software, eqmod ?....

if using external knobs to the Synscan software, then no, there will be no update on the Synscan display....

1.5 mm across the flats ?? I doubt there is one, the smallest I know of is 3mm.....

If the menu doesn't show what you want, it my be worth installing Magic Lantern (Magic Lantern | Home) onto the SD card, as this software 'exposes' more of the in-built functions....

Did you generate the STL files ? if so using what ? If not where did you download them from ? For something as large, and without the hardware that is to be mounted, it can difficult to ensure that everything will fit ok, with enough clearances for all the internal components....

Digikey have them TSL237S-LF ams | Sensors, Transducers | DigiKey

Personally, I'm always suspect of the devices used for charging in vehicles as I've found them over voltage & sometimes the Pi's can get upset.... So instead I use a dc-dc converter e.g. https://www.ebay.co.uk/itm/Better-Waterproof-DC-DC-Converter-12V-Step-Down-to-5V-Car-Power-Supply-Module-3A/133490822065?epid=14036484897 which I wire into the GPIO socket, but also means I can add additional safety components, if required, e.g. fuses, switches etc.

It probably doesn't need a 'split' coupler as that will introduce backlash, I find a straight coupler works fine.

...... and apparently it needs to be enabled, I believe that there is a series of posts on CloudyNights detailing how to enable it, after first setting the date\time.