andreasnoack, Harsha, thank you for your feedback! Even if I try to install GLM@1.3, I get several error messages. They are all about dependencies…! These seem to exist not only for JuliaPro, but also for Julia1.2.0. If I look at the file GLM-Compat.toml (but I have to admit, I have too little knowledge), then I see hints for different StatsModels versions:
["1-1.1"]
Distributions = "0.16-0"
Reexport = "0.1-0"
SpecialFunctions = "0.6-0"
StatsBase = "0.22-0"
StatsFuns = "0.6-0"
julia = "0.7-1"
["1.0"]
StatsModels = "0.2-0.5"
["1.1-1.2"]
StatsModels = "0.5"
["1.2-1"]
Reexport = "0.1-0.2"
julia = "1"
["1.2-1.3.0"]
Distributions = "0.16-0.19"
StatsBase = "0.30"
["1.2-1.3.1"]
SpecialFunctions = "0.6-0.7"
["1.2-1.3.3"]
StatsFuns = "0.6-0.8"
["1.3-1"]
StatsModels = "0.6"
["1.3.1-1"]
Distributions = "0.16-0.21"
StatsBase = "0.30-0.32"
["1.3.2-1"]
SpecialFunctions = "0.6-0.8"
["1.3.4-1"]
StatsFuns = "0.6-0.9"
StatsModels expects a DataFrames version that is quite different from the installed DataFrames v0.19.4 version:
["0-0.3"]
DataFrames = "0.11.5-0"
["0-0.5"]
Compat = "0.63-2"
StatsBase = "0.22-0"
julia = "0.7-1"
["0.4-0.5"]
DataFrames = "0.15-0"
["0.6-0"]
julia = "1"
["0.6-0.6.6"]
StatsBase = "0.22.0-*"
["0.6.7-0"]
DataAPI = "1.1.0-1"
DataStructures = "0.17"
ShiftedArrays = "1"
StatsBase = "0.22-0.32"
Tables = "0.2.11-0.2"
And here I think only the package maintainers can help. Also, I don’t think it makes sense to replace one package version with another until it fits. At the moment it’s just a friendly warning that the way it is called is out of date. It’s not nice, but it doesn’t seem to interfere with the calculations. Thus I hope for a solution by package adjustment by the caretakers. It’s certainly not an easy job and that’s why I find it impressive what the package creators do! 
Finally: I am currently trying to reinstall JuliaPro, but currently have GITHUB access problems.
Again, thank you!