@Louisw3 It is most likely that it is a 32/64 bit issue. A recent mac OS will I believe only run 64-bit.
If there was a choice in "Help" "Find externals" you will need the correct one for your system and it must match Pd 32/64 bit as well.
If you cannot find the correct one then you will need to compile it from a source file.
That should be easy on a Mac using "make" in a terminal.
A Google of "pure data timbreid source" will find what you need.
David.

@toddak Yes, you could be correct that starting the "symbol" "101vol01" with a "number" is confusing [route].
On my system it makes no difference, but it is the only difference between your patch and mine that I can see.
It's good that you have it working though.

You could see if the messages are going to the rightmost "rejection" outlet of [route] for your naming convention.
David.

@toddak The sliders are sending correctly...... it works fine on localhost.
Maybe a firewall setting on the receiving computers? assuming you have the correct addresses...... connect 192.168.1.101 9001..... and connect 192.168.1.103 9001
Check that Pd has been allowed through the firewall for "private" or "local" connections on all the computers.
If you are running Windows a box would have popped up when you first ran Pd asking for that permission and maybe you clicked "no".

I don't know what the options in "firewall" "advanced" are on a mac, but at least the "Block all incoming connections" will need to be deselected for Pd.darwin.
David.

@Butahuruf If you could prefer Mobius there are some images available for the RPI which include "wine".......... and so you can run Linux and a Windows emulation on the RPI and then run Mobius or run the Mobius VST within Pd in windows.
David.

@Help Do you have a Scandinavian keyboard or a German Mac keyboard and the layout has changed?
Otherwise maybe update to Pd 0.50-2 ....... https://forum.pdpatchrepo.info/topic/1520/pure-data-windows/7
0.50-2 here....... http://msp.ucsd.edu/software.html
David.

@Butahuruf Not yet, as very little time the last few days.
I will give it another bash at the weekend.
David.

@Nanook2121 Good. Open a powershell or cmd window, and type "choco install make" and then you can use the make command.
AArgh.
Looking at the makefile.nt it requires that the .cpp files have been compiled to .obj files before it runs.
The script seems to have been made for Microsoft Visual Studio 11.
I will try it at the weekend and post back...... a lot of learning to do.
You might succeed before me.

BUT....
As you are using Windows you could run the portable (not installed) version of 32-bit Pd Extended and run TUIO in that. It will not clash with your Vanilla installation.
If you have to run Vanilla at the same time you can communicate between the twoPd's using [netsend] and [netreceive].
The Portable Extended is here........ http://puredata.info/downloads/pd-extended
The second one...... 52.7Mb (run anywhere).
Unzip it and put it where you wish...... on the Desktop? or anywhere.... even an external drive.
To use it for TUIO you need then to open pd.exe in its "bin" folder and use the terminal menu to "open" the TUIO patches.
David.

@Nanook2121 Your system is therefore 64-bit.
In osx or Linux you can follow what @teo523 figured out above.
In osx or Linux you can do the same and type "make pd_nt" for a windows .dll compilation, and then copy the created files over to your windows system.
In windows there are slightly more complex tools.
The easiest is probably Chocolaty.... https://stackoverflow.com/questions/32127524/how-to-install-and-use-make-in-windows
and the link will take you to https://chocolatey.org/install
Not easy to install, but once you have it installed you will be able to compile other stuff easily.
If you go the "completely offline install" route you will need to unzip a .nupkg file (something like https://www.7-zip.org/download.html where there is a standalone..... not installed version..... will do that).
David.

@toddak [netsend] and [netreceive] still work pretty much as they did in Extended, just the parameters have changed in Vanilla I think for udp tcp etc. formatting.
OSC messaging is a bit more difficult in Vanilla especialy because of a problem sending a float as part of the message header. The float arrives as a symbol and so cannot be routed simply.
Here are [netsend] and [netreceive] tests and an OSC patch that solves the float problem.......
It seems you are not using the OSC though.
Make sure the send is to a fixed IP address for the other computer, and use [list prepend] instead of [prepend] for Vanilla.
vanilla osc.zip
Upload the patch if you are still having problems.
David.

@yannseznec @beep-beep is correct. But you can use # instead....... slider_#0 is the same as slider_$0 would be if it worked as expected.
David.