Separating Code, and Data databases in Installer Manifest using a containerized IRIS and durable %SYS feature

This is how Durable %SYS works, when it's initialized, it copies everything to the durable folder, including your db in mgr directory. And you can prevent it, by creating this database, just somewhere else.

Hello,
I have a similar problem, but the solution described here doesn't seem to solve it. 
I have installer.cls with manifest in it, where I create namespace and 2 db's (for code - updatable and data - durable). In docker-compose I use ISC_DATA_DIRECTORY to set durable volume. Also I use module.xml to create web application and load code.
I tried to set my code db permissions to read-only in iris.script after I setup new namespace and db's but then I have errors when loading classes to db. 
I'm pretty new to IRIS, so will be grateful for any suggestions. Thank you.
iris.script

ZN"%SYS"Do$system.OBJ.Load("/opt/irisapp/App.Installer.cls","ck")
    Do##class(App.Installer).Setup()

    ZN"STORE"Do$System.OBJ.LoadDir("/opt/irisapp/src", "ck","",1)

    //ZN "%SYS"//Do ##class(App.Installer).SetupDBPermissions("/code/storeCode/", 1)zn"%SYS"do##class(Security.Users).UnExpireUserPasswords("*")
    do##class(Security.Roles).Create("CustomAdmin", "Custom admin role for OGS application")
    do##class(Security.Roles).Create("Purchaser", "Custom purchaser role for OGS application")
    do##class(Security.Users).Create("CustomSuperUser%40admin.com", "%All,customadmin", "password", "Custom SuperUser")
    do##class(Security.Users).AddRoles("SuperUser", "%all,customadmin", 1)

    zn"STORE"do##class(GroceryApp.utils.Seed).SeedRegions()
    do##class(GroceryApp.data.Category).AddMultipleCategories()

    zpm "load /opt/irisapp/ -v":1:1halt

App.Installer.cls

Class App.Installer
{
XData setup
{
    <Manifest>
        <Default Name="Namespace" Value="STORE" />
        <Default Name="app" Value="store" />
        <If Condition='(##class(Config.Namespaces).Exists("${Namespace}")=0)'>
            <Namespace Name="${Namespace}" Create="yes" Code="${Namespace}CODE" Data="${Namespace}DATA" Ensemble="">
                <Configuration>
                    <!-- Durable data database -->
                    <Database Name="${Namespace}DATA"
                            Dir="${app}Data"
                            Create="yes"
                            MountRequired="true"
                            Resource="%DB_${Namespace}DATA"
                            PublicPermissions="RW"
                            MountAtStartup="true" />

                    <!-- Non-durable code database -->
                    <Database Name="${Namespace}CODE"
                            Dir="/code/${app}Code"
                            Create="yes"
                            MountRequired="true"
                            Resource="%DB_${Namespace}CODE"
                            PublicPermissions="RW"
                            MountAtStartup="true" />
                </Configuration>
            </Namespace>
        </If>

        <Namespace Name="USER" Create="no" Code="USER" Data="USER" Ensemble="0">
            <Configuration>
                <ClassMapping From="${Namespace}CODE" Package="GroceryApp" />
                <RoutineMapping From="${Namespace}CODE" Routines="GroceryApp" />
            </Configuration>
        </Namespace>

    </Manifest>
}

ClassMethod Setup(ByRef pVars, pLogLevel As%Integer = 0, pInstaller As%Installer.Installer) As%Status [ CodeMode = objectgenerator, Internal ]
{
    Quit##class(%Installer.Manifest).%Generate(%compiledclass, %code, "setup")
}

/// Change database permissions/// <ul>/// <li><var>dbDir</var> Path to the database.</li>/// <li><var>mode</var> Permission mode. 0 = read/write, 1 = read-only. Optional</li>/// </ul>ClassMethod SetupDBPermissions(dbDir as%String, mode as%Integer = 0) As%Status {
  New$NAMESPACESet$NAMESPACE = "%SYS"Set sc = $$$OKSet db = ##class(SYS.Database).%OpenId(dbDir)
  Write"Setting database permission for " _ db.Directory _ ". Setting ReadOnly from " _ db.ReadOnly _ " to " _ mode, !
  Set db.ReadOnly = mode
  $$$ThrowOnError(db.%Save())

  Return sc
}
}