Yeah, that is a bug with the alpha release client when joining a modded server, if it happens, just do /reconnect and then you should connect fine.

Also, for improved graphics, make sure you have these settings (you may or may not have to set them for each different "mods" you join):

```
/cl_renderer "opengl2"
/r_cubeMapping 1
/r_normalMapping 1
/r_sunlightMode 2
/r_sunShadows 1
```

Here are all the rendering settings I use at the moment if it helps:

```
r_smp = "0"
r_primitives = "0"
r_ignoreFastPath = "1"
r_availableModes = "640x360 720x405 864x486 960x ... x384 640x480 800x600 1024x768"
r_sdlDriver = "x11"
r_allowSoftwareGL = "0"
r_maxpolyverts = "3000"
r_maxpolys = "600"
r_noportals = "0"
r_lockpvs = "0"
r_drawBuffer = "GL_BACK"
r_offsetunits = "-2"
r_offsetfactor = "-1"
r_clear = "0"
r_shownormals = "0"
r_showsky = "0"
r_showtris = "0"
r_nobind = "0"
r_debugSurface = "0"
r_logFile = "0"
r_verbose = "0"
r_speeds = "0"
r_showcluster = "0"
r_novis = "0"
r_nocull = "0"
r_ignore = "1"
r_drawentities = "1"
r_norefresh = "0"
r_lodscale = "5"
r_measureOverdraw = "0"
r_skipBackEnd = "0"
r_flareCoeff = "150"
r_flareFade = "7"
r_flareSize = "40"
r_portalOnly = "0"
r_lightmap = "0"
r_drawworld = "1"
r_nocurves = "0"
r_saveFontData = "0"
r_printShaders = "0"
r_debugSort = "0"
r_debuglight = "0"
r_showImages = "0"
r_directedScale = "1"
r_ambientScale = "0.6"
r_znear = "4"
r_singleShader = "0"
r_intensity = "1"
r_mapOverBrightBits = "2"
r_fullbright = "0"
r_forceSunAmbientScale = "0.5"
r_forceSunLightScale = "1.0"
r_forceSunMapLightScale = "1.0"
r_forceSun = "0"
r_cameraExposure = "0"
r_forceAutoExposureMax = "2.0"
r_forceAutoExposureMin = "-2.0"
r_forceAutoExposure = "0"
r_forceToneMapMax = "0.0"
r_forceToneMapAvg = "-2.0"
r_forceToneMapMin = "-8.0"
r_forceToneMap = "0"
r_externalGLSL = "0"
r_colorMipLevels = "0"
r_uiFullScreen = "0"
r_inGameVideo = "1"
r_allowExtensions = "1"
r_ext_compressed_textures = "0"
r_ext_multitexture = "1"
r_ext_compiled_vertex_array = "1"
r_ext_texture_env_add = "1"
r_ext_draw_range_elements = "1"
r_ext_multi_draw_arrays = "1"
r_ext_framebuffer_object = "1"
r_ext_texture_float = "1"
r_arb_half_float_pixel = "1"
r_arb_half_float_vertex = "1"
r_ext_framebuffer_multisample = "0"
r_arb_seamless_cube_map = "0"
r_arb_vertex_type_2_10_10_10_rev = "1"
r_arb_vertex_array_object = "1"
r_ext_texture_filter_anisotropic = "0"
r_ext_max_anisotropy = "2"
r_picmip = "0"
r_roundImagesDown = "1"
r_detailtextures = "1"
r_texturebits = "0"
r_colorbits = "0"
r_alphabits = "1"
r_stencilbits = "8"
r_depthbits = "0"
r_ext_multisample = "0"
r_overBrightBits = "1"
r_ignorehwgamma = "0"
r_mode = "-2"
r_fullscreen = "0"
r_noborder = "0"
r_width = "1366"
r_height = "768"
r_pixelAspect = "1"
r_simpleMipMaps = "1"
r_vertexLight = "0"
r_subdivisions = "4"
r_stereoEnabled = "0"
r_greyscale = "0"
r_hdr = "1"
r_floatLightmap = "0"
r_postProcess = "1"
r_toneMap = "1"
r_autoExposure = "1"
r_materialGamma = "1.0"
r_lightGamma = "1.0"
r_framebufferGamma = "1.0"
r_tonemapGamma = "1.0"
r_depthPrepass = "1"
r_ssao = "0"
r_normalMapping = "1"
r_specularMapping = "1"
r_deluxeMapping = "1"
r_parallaxMapping = "0"
r_cubeMapping = "1"
r_deluxeSpecular = "0.3"
r_specularIsMetallic = "1"
r_baseNormalX = "1.0"
r_baseNormalY = "1.0"
r_baseParallax = "0.05"
r_baseSpecular = "0.04"
r_baseGloss = "0.3"
r_dlightMode = "2"
r_pshadowDist = "128"
r_mergeLightmaps = "1"
r_imageUpsample = "0"
r_imageUpsampleMaxSize = "1024"
r_imageUpsampleType = "1"
r_genNormalMaps = "0"
r_drawSunRays = "1"
r_sunlightMode = "2"
r_sunShadows = "1"
r_shadowFilter = "1"
r_shadowMapSize = "1024"
r_shadowCascadeZNear = "8"
r_shadowCascadeZFar = "1024"
r_shadowCascadeZBias = "0"
r_ignoreDstAlpha = "1"
r_lodCurveError = "250"
r_lodbias = "0"
r_flares = "0"
r_zproj = "64"
r_stereoSeparation = "64"
r_ignoreGLErrors = "1"
r_fastsky = "0"
r_drawSun = "0"
r_dynamiclight = "1"
r_dlightBacks = "1"
r_finish = "0"
r_textureMode = "GL_LINEAR_MIPMAP_LINEAR"
r_swapInterval = "0"
r_gamma = "1"
r_facePlaneCull = "1"
r_railWidth = "16"
r_railCoreWidth = "6"
r_railSegmentLength = "32"
r_anaglyphMode = "0"
r_mergeMultidraws = "1"
r_mergeLeafSurfaces = "1"
r_marksOnTriangleMeshes = "0"
r_aviMotionJpegQuality = "90"
r_screenshotJpegQuality = "90"
r_allowResize = "0"
r_centerWindow = "0"
```