Yesterday I consulted some further reference books
with respect too the ON word "alls", and was thus
able to answer my own question to some extent.
I will relate what I found below, since it may be of
interest to others as well.
The context was Vögg's statement in the Saga of Rolf Krake:
"Alls ekki hefi ek til, því at ek em félauss."
First note that some dictionaries list "alls" under the
equivalent form "alz".
Then I went looking for translations of the saga text
and found two: one by Paul Herrmann and another by
Jesse Byock, who give the following German and English
translations of Vögg's sentence:
« Dazu habe ich gar nichts, da ich ein armer Mann bin.
So muß der dem anderen geben, der es dazu hat. » (PH)
« I have nothing to give, because I am a man without property.
He who has must give. » (JB)
Since P.H.'s translation is clearly more faithful to the
Old Norse text, I will attempt to give an English version
of the German translation:
« For such I have nothing at all, since I am a poor man.
Then must he give to the other, who posesses [it for] such. »
Then compare to the Old Norse text:
« Alls ekki hefi ek til, því at ek em félauss.
Sá hlýtr þá at gefa öðrum sem til á. »
We see then that "alls ekki" here forms a phrase that may mean
"nothing at all". Also note that the word "til" may then be
taken to mean "for such".
With respect to the word alz = alls, I found the following
information after leafing through several grammar texts.
The adverb "alls" = the neutrum singular genitive of the
adjective "allr" and has been formed from the latter through
one of the several mechanisms that were used in Old Norse to
form adverbs from adjectives. Another example of the same
scheme is the adverb "þvers" which has been formed by taking
the neut. sg. gen. of the adjective "þverr".
According to Zoëga this word may be written in English as
across or as athwart. 'Brjóta eineð þvers um' and 'Hann snýr
þvers af leiðinni' are supposed to be examples of the use of
the adverb, and 'Hann kvazt ekki þverr vera í því at selja
skipit' is supposed to be an example of the adjective.
I suppose much more could be said about it, for example
how this word occurred in the other Germanic languages
as MHG "twerch" > G "quer", D "dwars", N "tver", "tvers"
etc. How do you for example translate "treet låg på tvers
av vegen" into Icel. or ON? (the tree lay across the road)
Or "han gav meg eit tvert svar" (he gave me an unfriendly
answer). And what about the adverb þvert? (þvert í móti
= "on the contrary"). Is it used only in modern Icel. and
not in Old Norse?
In the same way, the pair allr-alls could also be illustrated
by many small sentences. I know for example that the Swedes
use "alls" in a way that it is not in Danish or Norwegian.
(inte alls = "not at all" I believe) Well, I am not sure
how great the interest is for such. Personally I find such
"little words" not all that easy to learn, because usage
can vary considerably from language to laguage, even if the
words are the same.