why "type not found" inside haxeflixel project, when i try to "import assets.manager.FileLoader;"?

Question

i use haxeflixel and syntax import assets.manager.FileLoader;
after this i have error "type not found" my steps
1- terminal "haxelib install assetsmanager" ... done
2- Project.xml <haxelib name="assetsmanager" />
3- inside PS.hx "import assets.manager.FileLoader;"
third step create error . vscode terminal show me this

> Executing task: haxelib run lime test cpp -debug <

Called from ? line 1
Called from CommandLineTools.hx line 1400
Called from CommandLineTools.hx line 25
Called from a C function
Called from CommandLineTools.hx line 126
Called from CommandLineTools.hx line 619
Called from lime/project/PlatformTarget.hx line 70
Called from lime/tools/platforms/LinuxPlatform.hx line 300
Called from lime/project/HXProject.hx line 244
Called from lime/project/ConfigData.hx line 35
Called from lime/tools/helpers/ObjectHelper.hx line 127
Called from lime/tools/helpers/ObjectHelper.hx line 127
Called from lime/tools/helpers/ObjectHelper.hx line 127
Called from lime/tools/helpers/ObjectHelper.hx line 76
Called from /usr/share/haxe/std/neko/_std/Array.hx line 118
Uncaught exception - Invalid operation (+)
Процесс терминала завершен с кодом выхода: 1

this is function from Array.hx source

    public function push(x:T) : Int {
        var l = this.length;
        this.__grow(l + 1);  //line 118
        this.__a[l] = x;
        return l + 1;
    }

i use vscode 1.20.1 , ubuntu 16.04.3 x64, and import syntax from this link
https://github.com/tiagolr/assetsmanager/blob/master/tests/TestLoadFiles.hx

my lime 2.9.1 was rebuilded from source, that support api26 for android targeting.

full configuration

haxe 3.4.4
nekoVM 2.1.0

haxelib 3.3.0
assetsmanager: [1.2.0]
async: [0.3.0]
flixel-addons: [2.5.0]
flixel-demos: [2.4.3]
flixel-templates: [2.4.6]
flixel-tools: [1.4.1]
flixel-ui: [2.2.0]
flixel: [4.3.0]
format: [3.4.0]
hxcpp: [3.4.64] 3.4.188
lime-samples: [4.0.1]
lime: [2.9.1] rebuilded from source as i said above
mlib: [2.0.2]
msignal: [1.2.4]
openfl: [3.6.1]