MATLAB: Use older MATLAB save formats

MATLABsave

I'm running a model that has a bunch of DLLs which read some .mat files.
When I use an old version of MATLAB (I think 2011a) to generate the files I get files that work okay, but when I create them with 2017a the files seem not to work with the same script.
I've used 2017 to read in the working 2011 file and then save it, and these files also don't work.
I've also tried the above with the '-vXX' settings at all available values according to the help, with no success.
Example:
clear; load('v2011file.mat'); save('v2017copy.mat', '-v6', 'var1', 'var2', 'var3');
One thing that I have notices between the two is that when they're selected in the "Current folder" browser, the preview always shows the 2017 files with the variable names in aphabetical order, regardless of the order that I saved them in, while the older 2011 file seems to maintain the order that they were saved. I can only assume that this is something related to a change in the way that files are saves – it might not be a problem but it does hint toward a change (it does this whether or not I include '-vXX' to use older formats).
It's probably worth noting that the 2011 files are created on XP, while the 2017 files are made on Windows 7.
Essentially I'm looking for anyone who might know whether it's possible for me to change the way that the file is put together by MATLAB, rather than having to change the DLLs to acceps a newer file.

Best Answer

It looks like I can work around the save order issue and have something that works by doing:
save('new2017file.mat', 'var1');
save('new2017file.mat', 'var3'. '-append');
save('new2017file.mat', 'var2', '-append');
Meaning I can put them in a specific order - I have to have the default save set to -v7 in preferences>general>.mat files too.
I wouldn't say no to a more elegant answer if there's one available though!
Related Question