nxm:// handler doesn't work with Mod Organizer 2.5.2

[mysticfall]

If I update Mod Organizer 2 from version 2.5.0 (the default version the installer downloads) to 2.5.2, nxmhandler.exe ceases to function.

When I launch nxmhandler.exe with protontrick without any argument, it shows the registration window with the correct entries. But specifying an nxm:: URL fails with the following log:

11월 28 15:31:21 mysticfall steam-runtime-launch-client[46940]: wine: using kernel write watches, use_kernel_writewatch 1.
11월 28 15:31:21 mysticfall steam-runtime-launch-client[46940]: 0320:err:kerberos:kerberos_LsaApInitializePackage no Kerberos support, expect problems
11월 28 15:31:21 mysticfall steam-runtime-launch-client[46940]: 0320:err:ntlm:ntlm_LsaApInitializePackage no NTLM support, expect problems
11월 28 15:31:21 mysticfall steam-runtime-launch-client[46940]: 0320:fixme:win:RegisterPowerSettingNotification (00000000002500AE,{02731015-4510-4526-99e6-e5a17ebd1ae>
11월 28 15:31:21 mysticfall steam-runtime-launch-client[46940]: 0320:fixme:setupapi:SetupDiOpenDeviceInterfaceW flags 0x1 not implemented
11월 28 15:31:21 mysticfall steam-runtime-launch-client[46940]: 0320:fixme:combase:RoGetActivationFactory (L"Windows.UI.ViewManagement.UISettings", {00000035-0000-000>
11월 28 15:31:21 mysticfall steam-runtime-launch-client[46940]: 0320:fixme:ui:factory_QueryInterface {94ea2b94-e9cc-49e0-c0ff-ee64ca8f5b90} not implemented, returning>
11월 28 15:31:21 mysticfall steam-runtime-launch-client[46940]: 0320:fixme:combase:RoGetActivationFactory (L"Windows.UI.ViewManagement.UISettings", {00000035-0000-000>
11월 28 15:31:21 mysticfall steam-runtime-launch-client[46940]: 0320:fixme:ui:factory_QueryInterface {94ea2b94-e9cc-49e0-c0ff-ee64ca8f5b90} not implemented, returning>
11월 28 15:31:21 mysticfall steam-runtime-launch-client[46940]: 0320:err:exec:SHELL_ExecuteW cannot set directory L"Z:\\home\\mysticfall\\\"Z:\\home\\mysticfall\\\d50>
11월 28 15:31:22 mysticfall steam-runtime-launch-client[46943]: wine: using kernel write watches, use_kernel_writewatch 1.
11월 28 15:31:22 mysticfall steam-runtime-launch-client[46940]: 0320:fixme:win:UnregisterPowerSettingNotification (00000000DEADBEEF): stub
11월 28 15:31:22 mysticfall steam-runtime-launch-client[46943]: 03ec:err:kerberos:kerberos_LsaApInitializePackage no Kerberos support, expect problems
11월 28 15:31:22 mysticfall steam-runtime-launch-client[46943]: 03ec:err:ntlm:ntlm_LsaApInitializePackage no NTLM support, expect problems
11월 28 15:31:22 mysticfall steam-runtime-launch-client[46943]: 03ec:fixme:file:RtlDosPathNameToRelativeNtPathName_U_WithStatus Unsupported parameter
11월 28 15:31:22 mysticfall steam-runtime-launch-client[46943]: 03ec:fixme:thread:GetThreadUILanguage : stub, returning default language.
11월 28 15:31:22 mysticfall steam-runtime-launch-client[46943]: 03ec:fixme:nls:RtlGetThreadPreferredUILanguages 00000038, 000000000011C9EC, 0000000000000000 000000000>
11월 28 15:31:22 mysticfall steam-runtime-launch-client[46943]: 03ec:fixme:nls:get_dummy_preferred_ui_language (0x38 0x412 000000000011C9EC 0000000000000000 000000000>
11월 28 15:31:22 mysticfall steam-runtime-launch-client[46943]: 03ec:fixme:nls:RtlGetThreadPreferredUILanguages 00000038, 000000000011C9EC, 0000000000CE19C0 000000000>
11월 28 15:31:22 mysticfall steam-runtime-launch-client[46943]: 03ec:fixme:nls:get_dummy_preferred_ui_language (0x38 0x412 000000000011C9EC 0000000000CE19C0 000000000>
11월 28 15:31:22 mysticfall steam-runtime-launch-client[46943]: 03ec:err:module:loader_init "LIBBSARCH.dll" failed to initialize, aborting
11월 28 15:31:22 mysticfall steam-runtime-launch-client[46943]: 03ec:err:module:loader_init Initializing dlls for L"Z:\\home\\mysticfall\\\d504\b85c\adf8\b7a8\\modorg>