ExtJs : Migration to 6.5 from 6.2.1: $'{'framework.name'}'.properties does not exist - upgrade

Question

My current ExtJs application is built with version 6.2.1.
I installed the new Sencha Cmd 6.5
and also the ExtJS 6.5 framework, on this directory: "D:\TOOLS\Sencha\ext-6.5.0".
But when I launched the upgrade command :
sencha app upgrade -ext -path "D:\TOOLS\Sencha\ext-6.5.0"
First of all I've the following warning:
[WRN] Disabling framework : current version 6.5.0.775 is incompatible with required version 6.2.1.167
And then the build failed on this error
com.sencha.exceptions.ExNotFound: Required property file D:\AllAtrium\trunk\Web\src\trunk\FrontExtJs.sencha\app\$'{'framework.name'}'.properties does not exist
This missing variable is nevertheless declared into the file "MyApp\ext\cmd\sencha.cfg".
How to solve this issue ?
Is there a another way to migrate an app from v6.2 to v6.5 ?
Full log :
Sencha Cmd v6.5.0.180
[WRN] D:\Web\src\trunk\FrontExtJs\.sencha\app contained customized file Microloader_orig.js
[WRN] D:\Web\src\trunk\FrontExtJs\.sencha\app contained customized file sencha.cfg.bak
[WRN] Directory D:\Web\src\trunk\FrontExtJs\.sencha\app could not be removed
[INF] Loading configuration for framework directory: D:\TOOLS\Sencha\ext-6.5.0
[INF] Copying framework to D:\Web\src\trunk\FrontExtJs\ext
[INF] Upgrading to Ext JS 6.x
[INF] Upgrading to sdk at D:\TOOLS\Sencha\ext-6.5.0
[INF] Updating application and workspace from Ext JS 6.2.1.167 / Cmd 6.2.1.29
[WRN] Disabling framework : current version 6.5.0.775 is incompatible with required version 6.2.1.167
[ERR]
[ERR] BUILD FAILED
[ERR] com.sencha.exceptions.ExNotFound: Required property file D:\Web\src\trunk\FrontExtJs\.sencha\app\$'{'framework.name'}'.properties does not exist
[ERR]
[ERR] Total time: 0 seconds
[ERR]
[ERR] BUILD FAILED
[ERR] com.sencha.exceptions.BasicException: com.sencha.exceptions.ExNotFound: Required property file D:\Web\src\trunk\FrontExtJs\.sencha\app\$'{'framework.name'}'.properties does not exist
[ERR]
[ERR] Total time: 1 second
[ERR] com.sencha.exceptions.BasicException: com.sencha.exceptions.ExNotFound: Required property file D:\Web\src\trunk\FrontExtJs\.sencha\app\${framework.name}.properties does not exist
[ERR]
[ERR] The application was last modified by an older version of Sencha Cmd (6.2.1.29).
[ERR] Running "sencha app upgrade" may resolve the error described above.
[ERR]

Answer 1

My answer might come too late but at least maybe it will help others:
I have upgraded a fair number of applications till now (major & minors including nightly builds) and I was rarely able to upgrade an app without Errors using the Sencha Guide.
I found that it is much easier and less time consuming to:
generate another application with the same name
copy (almost) all your files & folders into the new app (/app except Application.js, /overrides, /resources, /sass etc.)
manually change (merge) app.json file and Application.js file from the 2 apps - framework specific declarations might differ.
run an application build
Note1: Upgrade to the latest Sencha Cmd version (for simplification).
Note2: sencha upgrade installs the newer version if exists but does not uninstall the older one(s). Make sure you are using the latest one.

Answer 2

I had to run sencha app install which will repopulate missing files. Once I ran that, sencha app upgrade ran smoothly. Run sencha help app install for more info about it.