The reason for problems when choosing "Proceed" is because I did "self
error: 'bla'" instead of "^self error: 'bla'" so if you choose Proceed
it will actually try to install anyway, and then fails horribly. I fixed
this in my dev image, and will hunt down all similar errors I might have
- haven't really thought much about the distincion.

Further:
> Note that I am aware that installPackageNamed: should not be used any
> more. Is there a protocol which does exactly the same as the Package
> Loader if I click yes twice? The methods
> #installPackageLatestPublishedNamed: and
> #installPackageNamed:autoVersion: seem to do slightly different things.

"Yes twice" ought to mean that you want to install the latest release
regardless of the current image version or if it is not published. That
is not advisable to have in a load script since it will disable both
those mechanisms and cause unexpected problems for the user.

Note that I am aware that there are quite a few methods for installation
now and some overlap etc, I need to make this clearer. Anyway, my advice
is to either specify a specific release like this:

SMSqueakMap default installPackageNamed: 'Worlds Of Squeak Removal'
autoVersion: '1'

Since we are pointing at a specific release this will "bypass" the
checks if it is in fact published/not published or marked for the Squeak
version that the user has.

The other method you mention, #installPackageLatestPublishedNamed: and
it's sister method #installPackageLatestPublished: should IMHO probably
be removed. They don't check the Squeak version and probably only
confuse things.

Ok, if you don't want to specify a specific release - then the
installPackageNamed: would work *iff* there was a published release of
"Worlds Of Squeak Removal" that also was marked for Squeak 3.7.

So given the two "safety mechanisms" we have now - the check for
published, and the check for correct Squeak version - the
install-methods that do not specify a specific release are much more
"ok" to use.

regards, Gšran

PS. Will see if I can write a little SqP article on this subject later
today.