Hi Erds. I'm not sure if that procedure ('001 commands...in the "DVR" device, and 002 in the "DVD" device') is just a long winded way of changing 'A/V inputs', individually aka 'Hdmi1', 'Hdmi2' etc.
The address change command sent out is global and is not device specific. Even with the unintended DVR+ turned off with power connected, the command will change all of your units at once...
As mdavej has said recently, sending an input command can often also act as a discrete 'power on' command to the device which is connected by the respective input
i.e. sending it when the device is already powered on does not act to toggle power to 'off'.
With JP1 the term 'global' can be used to describe a 'macro', which is a sequence of various commands, whether for a single device or several different devices.
When a global macro is assigned to a button it gets sent when the remote is in any device mode.
Luckily RCRP05BR can also assign DSMs ('device specific macros') to its buttons, which only get sent when the remote is in a specifc device mode.
This will all become clearer when you can actally use JP1's GUI program, 'RMIR', but you will have already seen:-
RMIR opens in the 'General' tab where, by clicking the 'File' button at top left, you can get a wizard for loading an 'Upgrade' file for each of your devices (to be found in the File Section here).
There are other tabs, including 'Keymoves', 'Macro' (for setting up global versions), 'Special Functions' (for RCRP05BR the only available special function is DSM), and 'Devices', where the default button assignments can be edited.
When you load an upgrade the wizard invites you to specify which button to use (for setting the RCRP05BR's mode to that device) but, in the Layout page of Device> Edit, you can also assign any of that device's keys to a Device Button, including its input commands (which become global when assigned to a device button, so pressing a device button can also set the input for that device).
Usefully the input keys can also be assigned to Shifted buttons, perhaps for use in macros, or in the Keymoves tab to buttons in other devices.
Eventually you may find it useful to put a DSM on a non-device-button 'n' to include setting the remote's mode to another device and the TV device's input for that device (and/or input for other other mediator device/s).
Then, in the target device, put a DSM on the same button 'n' for return to the first device mode with the appropriate inputs set back again.
Having said all that I'm not sure if, without employing an extender, you could just put a DSM on a device button

and would welcome correction to avoid misleading anyone.