example causes R segfault

I came across this package a while ago and finally got around to taking it for a test drive. I was quite excited about making hex stickers for several of my own packages, but, unfortunately, upon trying it out today, I discovered I cannot even run the example (for working with image files) in the README relevant to my intended use case:

❯ imgurl <- "http://www.belleamibengals.com/bengal_cat_2.png"
❯ sticker(imgurl, package="hexSticker", p_size=8, s_x=1, s_y=.75, s_width=.6, filename="./imgfile.png")

 *** caught segfault ***
address 0x0, cause 'unknown'

Traceback:
 1: grid.Call.graphics(C_text, as.graphicsAnnot(x$label), x$x, x$y,     resolveHJust(x$just, x$hjust), resolveVJust(x$just, x$vjust),     x$rot, x$check.overlap)
 2: drawDetails.text(x, recording = FALSE)
 3: drawDetails(x, recording = FALSE)
 4: drawGrob(x)
 5: recordGraphics(drawGrob(x), list(x = x), getNamespace("grid"))
 6: grid.draw.grob(x$children[[i]], recording = FALSE)
 7: grid.draw(x$children[[i]], recording = FALSE)
 8: drawGTree(x)
 9: recordGraphics(drawGTree(x), list(x = x), getNamespace("grid"))
10: grid.draw.gTree(x$children[[i]], recording = FALSE)
11: grid.draw(x$children[[i]], recording = FALSE)
12: drawGTree(x)
13: recordGraphics(drawGTree(x), list(x = x), getNamespace("grid"))
14: grid.draw.gTree(gtable)
15: grid.draw(gtable)
16: print.ggplot(x)
17: print(x)
18: grid.draw.ggplot(plot)
19: grid.draw(plot)
20: ggsave(sticker, width = 43.9, height = 50.8, filename = filename,     bg = "transparent", units = "mm")
21: save_sticker(filename, sticker)
22: sticker(imgurl, package = "hexSticker", p_size = 8, s_x = 1,     s_y = 0.75, s_width = 0.6, filename = "./imgfile.png")

Possible actions:
1: abort (with core dump, if enabled)
2: normal R exit
3: exit R without saving workspace
4: exit R saving workspace

I'm not exactly sure what might be going on internally, so some help in diagnosing and resolving this problem would be much appreciated.

Here's the relevant session information:

❯ sessionInfo()
R version 3.4.1 (2017-06-30)
Platform: x86_64-apple-darwin16.6.0 (64-bit)
Running under: macOS Sierra 10.12.5

Matrix products: default
BLAS: /System/Library/Frameworks/Accelerate.framework/Versions/A/Frameworks/vecLib.framework/Versions/A/libBLAS.dylib
LAPACK: /System/Library/Frameworks/Accelerate.framework/Versions/A/Frameworks/vecLib.framework/Versions/A/libLAPACK.dylib

locale:
[1] en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

other attached packages:
 [1] hexSticker_0.4.1     forcats_0.2.0        stringr_1.2.0.9000  
 [4] dplyr_0.7.2          purrr_0.2.2.2        readr_1.1.1         
 [7] tidyr_0.6.3          tibble_1.3.3         ggplot2_2.2.1       
[10] tidyverse_1.1.1.9000 devtools_1.13.2.9000 nima_0.4.0          
[13] fcuk_0.1.21          colorout_1.1-2       prompt_1.0.0        

loaded via a namespace (and not attached):
 [1] locfit_1.5-9.1       Rcpp_0.12.12         stringdist_0.9.4.4  
 [4] lubridate_1.6.0.9009 lattice_0.20-35      sysfonts_0.6        
 [7] fftwtools_0.9-8      png_0.1-7            clisymbols_1.2.0    
[10] gtools_3.5.0         assertthat_0.2.0     digest_0.6.12       
[13] psych_1.7.5          tiff_0.1-5           R6_2.2.2            
[16] cellranger_1.1.0     plyr_1.8.4           httr_1.2.1          
[19] rlang_0.1.1.9000     lazyeval_0.2.0       readxl_1.0.0        
[22] data.table_1.10.4    rstudioapi_0.6       ProjectTemplate_0.7 
[25] hexbin_1.27.1        boxes_0.0.0.9000     foreign_0.8-69      
[28] munsell_0.4.3        broom_0.4.2          compiler_3.4.1      
[31] modelr_0.1.0         gridGraphics_0.2     pkgconfig_2.0.1     
[34] BiocGenerics_0.22.0  mnormt_1.5-5         pkgbuild_0.0.0.9000 
[37] gridExtra_2.2.1      showtextdb_1.0       crayon_1.3.2.9000   
[40] withr_1.0.2          grid_3.4.1           nlme_3.1-131
[43] jsonlite_1.5         gtable_0.2.0         DBI_0.7             
[46] magrittr_1.5         scales_0.4.1.9002    stringi_1.1.5       
[49] reshape2_1.4.2       ggthemes_3.4.0       bindrcpp_0.2        
[52] xml2_1.1.1           EBImage_4.18.0       tools_3.4.1         
[55] showtext_0.4-6       glue_1.1.1           jpeg_0.1-8          
[58] hms_0.3              abind_1.4-5          pkgload_0.0.0.9000  
[61] parallel_3.4.1       colorspace_1.3-2     rvest_0.3.2         
[64] ggimage_0.0.4        memoise_1.1.0        bindr_0.1           
[67] haven_1.1.0   

Start with the image-file example in the README and reproduce the crash using sticker() with the reported sessionInfo. Trace the failure from sticker() through ggsave() and grid drawing; done means the example completes without a segfault and writes imgfile.png.