iSphere v6.0.6.r install failed

I installed RDi 9.8 on my new Win11 laptop. (I unzipped IBM_Rational_Developer_for_i-9.8.0.0.zip into C:\, so that rdi.exe is in folder "C:\IBM Rational Developer for i".) I used my normal profile. I installed all five fixpacks and am now at v9.8.0.5. Due to firewall, I am unable to install iSphere via the update site. I found iSphere for RDi 9.5.1.3+ (v6.0.6.r Update Site).zip at rdi-open-source_github_io/isphere/files/. I tried installing using a Local Update Directory and using a Local Update Archive. Both attempts ended with:

An error occurred while collecting items to be installed
session context was:(profile=profile, phase=org.eclipse.equinox.internal.p2.engine.phases.Collect, operand=, action=).
An error occurred copying file C:\IBM_RDi_98\iSphere\v6.0.6.r\iSphere for RDi 9.5.1.3+ (v6.0.6.r Update Site)\plugins\org.eclipse.albireo.core_0.0.3.v20081031.jar.
C:\IBM_RDi_98\iSphere\v6.0.6.r\iSphere for RDi 9.5.1.3+ (v6.0.6.r Update Site)\plugins\org.eclipse.albireo.core_0.0.3.v20081031.jar (The system cannot find the file specified)
An error occurred copying file C:\IBM_RDi_98\iSphere\v6.0.6.r\iSphere for RDi 9.5.1.3+ (v6.0.6.r Update Site)\features\org.eclipse.albireo_0.0.3.v20081031.jar.
C:\IBM_RDi_98\iSphere\v6.0.6.r\iSphere for RDi 9.5.1.3+ (v6.0.6.r Update Site)\features\org.eclipse.albireo_0.0.3.v20081031.jar (The system cannot find the file specified)

Any ideas? Google was not my friend.

- Dan Bale
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